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(Ally Donnelly, NECN: Boston, MA) - A Boston hospital has received a grant to establish the world's first-ever center to study orphan diseases. An orphan disease is any disease or disorder affecting less than 200,000 people in the United States.
Because the disorders affect so few, researchers have a difficult time getting government or private funding. But as one Massachusetts family knows -- research can make the difference...between life and death
Andy Trevino just wants to play air hockey. Being dragged back to this hospital playroom and having a camera stuck in his face is not making things easier.
It's understandable that he's a little shy. The 8-year-old Sudbury, Massachusetts boy has had all the extra attention he needs in his young, tumultuous life.
Paulina, Mother: Two days after he was born, he got a fever and I thought, well, give him some Tylenol or something and that's it.
Unfortunately that would not be it. Andy -- born in Mexico City -- had a blood infection and would stay in the hospital's ICU for more than two weeks. When his parents finally brought their son home, they were not out of the woods.
Andres, Father: First it was a stomach infection then a central nervous system infection also known as meningitis, then he had pneumonia...
His infections were life threatening. Mexican doctors ran every test they could think of... But again and again they came up empty.
Paulina: It hurts a lot to see nurses and people poking at him all the time and watching him crying...
Andres: They were telling us that he had bad luck and we didn't take that for an answer.
The Trevino's had spent 375 days in the hospital in Mexico. Their money was dwindling, but not their hope. They had heard that Boston was the best -- so they came here, to Children's Hospital -- desperate for a medical miracle.
The moment we stepped into the ER, it felt safe.
The Trevino's met with a team of doctors and researchers at the renowned teaching hospital, which immediately went to work. The team soon discovered that Andy had a rare congenital disease. A glitch on one of his genes -- known as Nemo -- wasn't allowing his immune system to battle infection.
Alan Beggs, Children's Hospital: Because they had seen a large number of patients with an immune deficiency, they were able to predict what his defect might be and identify it for his family.
The family had few options. They could make Andy comfortable with medication, knowing his disease was terminal. They could get a transplant to replace his immune system or they could try and replace Andy's faulty cells with healthy cells from a new donor.
Unfortunately, they couldn't find a match trough the public donor registry for an immune system transplant and to replace Andy's unhealthy cells, they'd need a perfect donor -- like a sibling -- and Andy was an only child.
Andres: She was born March 14, 2004.
Though they knew some people would question their ethics, the Trevino's --- who had always planned on more children -- had Andy's sister -- and savior --- Sofia.
Andres: The first sound I heard when she cried were just the most incredible sound I've ever heard.
Children's doctors were able to take Sofia's bone marrow cells and infuse them into Andy's. Her healthy cells replaced his bad cells and his immune system rebuilt itself.
Andres: To see that he's cured, it's just...incredible.
Andy had what is known as an orphan disease -- a disease that affects less than 200-thousand people in the United States.
Beggs: In fact there may be only a few hundred patients or only a few 10s of patients with any particular disease, so it takes a center that sees a number of these things to bring these cases together.
Alan Beggs runs the new Manton center for orphan disease research. Established with a recent 25 million dollar gift to the hospital, it creates a dream team of researchers to work collaboratively.
The hope is that findings in the lab can translate into treatments in the field. Treatments not only for orphan diseases -- which are historically under funded, but a wide spectrum of conditions from cancer to Parkinson's. Take for example the stem cell researcher who has made significant advances in his own field.
He can create cells that could regenerate muscle for some of my patients or maybe regenerate nerves for some of the neurology patients and so on.
When the Trevino's came to children's in 2001, there was no Manton center, but they say their support will never waiver.
Andres: once they learn about it, they take it to the clinic and once they take it to the clinic they help more children and at the end of the day they save more lives.
More lives....like Andy's. He is now a thriving third grader who loves nothing more than playing with his best friend....his sister.
I also received this report regarding Bishops from Spain from hat seems to be a catholic news site.
Rapid translation: I'm disobedient.
Rapid translation: Too strong. Makes me mad.
Rapid translation: I'm selfish?
Specially disturbing, they said, is parents choosing a specific embryo because the child's tissues or organs might save the life of a sick sibling.
OOPS.
The Vatican isn't much for trying to save sick children's lives with embryonic stem cell research or PGD because they both mess with embryos and an embryo deserves the same respect as any adult. This is an old argument.
The best response is a perhaps over-used hypothetical scenario:
A building is burning down. Twelve small children are inside screaming for help. The building also contains a freezer storing a dozen or so frozen embryos. Which do you save first?
Spanish Bishops Condemn Creation of "Savior Sibling," Hand-picked for Optimal Genetic Material
By Kathleen Gilbert
MADRID, Spain, October 22, 2008 (LifeSiteNews.com) - A baby who was grown in order to donate umbilical cord blood to his ailing brother was born last week, an event that was widely reported in Spanish media. The renewed publicity given to the case has sparked criticism from the pro-life community and the Church who, while welcoming the birth of a newborn child, condemned the utilitarian mindset that surrounded the circumstances of his conception and birth.
Baby Javier Mariscal is the first "medicinal baby" to be born in Spain, carried to term in order to donate stem cells that may cure his six-year-old brother Andres, who has severe but non-fatal congenital anaemia. Javier was selected from among six embryos through a technique known as stem-cell selection, which determined that he did not inherit the condition, and could therefore grow stem cells in his umbilical cord that may help Andres. The remaining embryos were either frozen or killed and discarded.
In a statement published last weekend, the Spanish bishops blamed this controversial "savior sibling" method for depriving the remaining embryos of "the fundamental right to life" simply because they would not be able to help Andres. While some hailed Javier's birth as the next step in scientific progress, the bishops warned that it "reduced the dignity of the individual to a simple utilitarian value."
The bishops noted that the secular media has emphasized the good news of the child's birth, and remarked: "Put like this, the news ought to be a source of joy for all. However, the dramatic fact that the sick embryos, and eventually the healthy ones that were not genetically compatible were destroyed has been silenced.
"The Church wants to lend her voice to the voiceless and to those who have been deprived of the fundamental right to life," said the bishops, adding that their statements were not intended to judge, but to "draw attention to the objective ethical principles that protect the dignity of all human beings."
The Spanish pro-life community also reacted with dismay at the case. Manuel Cruz, director of the Life Foundation, told the Times Online, "The method of this birth is degrading for human beings to have been selected like a prize."
The Vatican issued a statement in L'Osservatore Romano following the child's birth, saying it was unjustifiable that parents had "sacrificed other possible children" in order to try curing Andres. About 80% of Spain's population is Catholic.
The case is the first of its kind after the Spanish parliament passed legislation in 2006 allowing the genetic selection of embryos.
The popularity of genetic screening to produce a "designer baby" like Javier is on the rise. However, many bioethicists consider screening for reasons of preference to undermine the intrinsic quality of human life, as it weighs the value of each baby's life according to his or her accidental traits.
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Girl in urgent need of bone marrow is saved by the sister born to help her live
By Alison Smith Squire and Nick McDermott
Last updated at 11:58 AM on 20th October 2008
Playing in the autumn leaves, Saskia Graham and her little sister Imogen look like any other happy, healthy youngsters.
But only 18 months ago Saskia was desperately ill with a debilitating blood disorder, in urgent need of a bone marrow transplant to save her life.
Fortunately, there was a ready-made donor - Imogen had been conceived as a 'saviour sibling' through the controversial process in which children are created so their tissue can be used to help a sick brother or sister.
For the girls' parents, however, the decision to use Imogen's bone marrow was still an agonising one. She was only 19 months old and would struggle to survive such an invasive procedure.
To their delight, the transplant worked - curing the blood disorder and creating what will be a lifelong bond between seven-year-old Saskia and Imogen, now three.
Their mother Natalie Barb, 38, said: 'The decision to operate was the most heart-wrenching one we have ever had to make.
'On the one hand, Saskia was growing sicker by the day and desperately needed a bone marrow transplant.
'On the other, the thought of tiny Imogen undergoing surgery was incredibly frightening.'
When Saskia was 11 weeks old she was diagnosed with Diamond Blackfan Anaemia, which is usually fatal before the age of 30. To lead a normal life, she would need a bone marrow transplant from a suitable donor before she turned six, when her condition would worsen.
Doctors told her mother and her father Stuart Graham, a 36-year-old banker, that their best chance was to find a match from a family member.
However, neither the couple, from West London, nor their second child, five-year-old Alice, were suitable.
So they made the controversial decision to create a saviour sibling - a baby genetically selected to be a perfect donor for a sick brother or sister.
Imogen was conceived by IVF using Pre-Implantation Genetic Diagnosis, a screening procedure which ensured she was an ideal match for Saskia.
'We were delighted when Imogen was born. Not only was she a beautiful little sister but she would be a suitable donor for Saskia,' said her mother, a TV producer. 'Her birth gave us the ray of hope we had longed for.' Even then, the decision to use her bone marrow was hard. 'Our fear was that something would go wrong and we would lose not only Saskia but Imogen as well.'
Doctors waited until Imogen was 19 months old and the surgery proved a success.
There has been huge controversy over saviour siblings. But Saskia's mother said: 'We will never regret ensuring that Imogen was a suitable donor. It is just an incredible bonus for us that medical science allowed us to ensure we could also save Saskia's life.'
Saskia is one of many children aged two to 18 treated by the specialist bone marrow transplant centre at St Mary's Hospital in London, part of Imperial College Healthcare NHS Trust, which this week celebrates its 18th anniversary.
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Nace en Andalucía el primer bebé libre de una enfermedad genética y compatible con su hermano, gravemente enfermo
La sangre de su cordón umbilical de Javier, el recién nacido, servirá para realizar el trasplante que necesita Andrés para superar una anemia congénita severa
El Hospital Virgen del Rocío de Sevilla ha acogido el nacimiento del primer bebé libre de una enfermedad genética hereditaria y que es compatible al cien por ciento con su hermano, de seis años de edad y enfermo de una grave dolencia, gracias al diagnóstico genético preimplantatorio. Se trata del primer procedimiento de estas características realizado íntegramente en España y va a posibilitar la curación de una persona, cuya única alternativa consiste en un transplante de médula ósea.
Andalucía fue la primera Comunidad Autónoma en incorporar el Diagnóstico Genético Preimplantatorio en la cartera de servicios del Sistema Sanitario Público Andaluz y desde la regulación de este procedimiento han nacido en la sanidad pública andaluza ocho pequeños libre de la enfermedad que les iba a transmitir sus padres. Javier, que se llama el recién nacido, es el noveno y supone un paso más en la técnica puesto que posibilita la curación de su hermano al ser inmunológicamente compatible.
La aprobación en 2006 de la Ley de Reproducción Humana Asistida abría paso a esta nueva opción terapéutica. El Sistema Sanitario Público Andaluz se ha puesto a la vanguardia al conseguir el nacimiento de Javier, el primer bebé de estas características cuyo tratamiento ha sido realizado en España. El alumbramiento de Javier tuvo lugar el pasado día 12 de octubre a las 11.35 horas. El niño ha pesado al nace 3,400 kilos.
El hospital sevillano es referente en Andalucía para la realización del diagnóstico genético preimplantatorio. Esta técnica, que se realiza en su Unidad de Genética y Reproducción Humana Asistida -dirigida por el doctor Guillermo Antiñolo-, consiste en la realización de un análisis genético a preembriones obtenidos por técnicas de fecundación in vitro antes de ser transferidos al útero de la madre, lo que posibilita seleccionar aquellos libres de la carga genética asociada a determinadas enfermedades.
En el caso de Javier, además de haberse evitado la transmisión de la enfermedad de la que son portadores sus padres y que padece su hermano, una anemia congénita severa (beta-Talasemia major), se ha conseguido que los dos hermanos sean perfectamente compatibles puesto que tienen idéntico perfil de histocompatiblidad (HLA), con lo que Javier es el donante idóneo para posibilitar la curación de Andrés mediante trasplante de cordón.
La sangre del cordón umbilical de Javier ha quedado almacenada en el Banco de Cordón Umbilical de Málaga, donde permanecerá hasta que el equipo médico programe el momento del trasplante de progenitores hematopoyéticos. La tasa de éxito de este procedimiento alcanza el 90% por lo que en unos meses, Andrés podrá hacer vida normal, dejando atrás la patología que padece. El pequeño, hasta ahora, no había respondido a ninguno de los tratamientos a los que se había sometido con lo que la donación de la sangre del cordón umbilical de Javier es la única opción terapéutica para el niño.
Diagnóstico genético preimplantatorio
El diagnóstico genético preimplantatorio es la técnica de reproducción asistida que permite evitar la transmisión de enfermedades genéticas hereditarias de padres a hijos. La Unidad de Gestión Clínica de Genética, Reproducción y Medicina Fetal de Hospitales Universitarios Virgen del Rocío es el servicio de referencia en Andalucía para la aplicación de esta técnica, en la que desarrollan su labor genetistas, embriólogos y ginecólogos.
El programa de Diagnostico Genético Preimplantatorio comenzó a funcionar en la comunidad en octubre de 2005, y desde entonces se han iniciado un total de 89 ciclos en 44 parejas. Se ha podido transferir al menos 1 embrión no afecto en 53 ciclos y se han conseguido 13 gestaciones clínicas, siendo la tasa de éxito del programa comparable a la de los mejores centros internacionales.
Desde que en julio de 2006 naciese en Andalucía el primer bebé libre de una enfermedad genética hereditaria en la sanidad pública, se han contabilizado un total de ocho recién nacidos mediante diagnóstico genético preimplantatorio, dos de ellos libres de distrofia muscular de Duchenne, 2 libres de hemofilia, 2 libres de fibrosis quística (parto gemelar) y 2 libres de enfermedad Huntington, a los que se suma el nacimiento de Javier, libre de beta-Talasemia major. Un segundo caso de diagnóstico genético preimplantatorio para que sea compatible con su hermano (DGP-HLA) está pendiente de la aprobación de la Comisión Nacional de Reproducción Humana Asistida.
El programa de Diagnóstico Genético Preimplantatorio, como el del Consejo Genético, se incluyen en el Plan Andaluz de Genética, una herramienta de trabajo que permitirá avanzar en las oportunidades que brinda el genoma humano en la prevención de enfermedades, su diagnóstico precoz e, incluso, el diseño de tratamientos a medida.
ANEXO
¿Qué es el Diagnóstico Genético Preimplantatorio y cómo se realiza?
El Diagnóstico Genético Preimplantatorio es un procedimiento que consiste en realizar un análisis genético a embriones obtenidos por técnicas de fecundación in vitro para transferir al útero únicamente aquellos libres de la enfermedad genética en estudio. En la actualidad constituye una opción reproductiva para familias con alto riesgo de transmitir enfermedades de base genética a sus hijos, siendo una buena alternativa al diagnóstico prenatal.
Además, el Diagnótico Genético Preimplantatorio abre nuevas vías en la prevención de enfermedades genéticas que carecen de tratamiento, al mismo tiempo que ofrece la posibilidad de seleccionar preembriones para que, en determinados casos y bajo el debido control y autorización, puedan servir para tratar la enfermedad del hermano enfermo.
La complejidad de esta técnica exige la colaboración estrecha de especialistas en Genética Médica y Reproducción Asistida. Hay que efectuar una biopsia del preembrión cuando éste tiene de 6 a 8 células. Las células extraídas se procesan para su análisis genético, que ha de ser rápido y preciso, pues los preembriones se deben transferir al útero en un tiempo limitado (dos días desde la biopsia). El análisis genético, mediante FISH y/o estudio molecular, indica qué preembriones pueden ser transferidos, ya que no desarrollarán la enfermedad para la que existe riesgo.
La técnica FISH y el análisis genético molecular
La hibridación in situ fluorescente (FISH) se emplea para prevenir la transmisión de enfermedades hereditarias graves ligadas al cromosoma X (hemofilia, distrofia muscular de Duchenne o síndrome de Alpont) mediante la selección de sexo. Consiste en marcar los cromosomas con sondas de ADN (ácido desoxirribonucleico) fluorescentes específicas para los cromosomas que se están estudiando. A continuación, con el microscopio de fluorescencia, se pueden identificar los cromosomas de interés.
El análisis genético molecular directo o indirecto del gen que produce la enfermedad mediante la reacción en cadena de la polimerasa (PCR) es útil para trastornos hereditarios graves con una mutación conocida (atrofia muscular espinal, fibrosis quística, corea de Huntington).
Consiste en la amplificación de secuencias específicas de un gen, en las que la presencia de una mutación desencadena una enfermedad de base genética. Permite diferenciar qué embriones no tienen un gen mutado y, por tanto, no desarrollarán la enfermedad. Es precisamente el análisis PCR el que permite en el Diagnóstico Genético Preimplantatorio garantizar el HLA idéntico.
¿Qué patologías pueden diagnosticarse?
La sanidad pública andaluza aplica actualmente el Diagnóstico Genético Preimplantatorio a las siguientes patologías: atrofia muscular espinal, distrofia muscular de Duchenne, enfermedad de Huntington, fibrosis quística, hemofilia A y B, síndrome de Alport ligado al cromosoma X y enfermedades hereditarias recesivas ligadas al cromosoma X.
La Comisión Andaluza de Genética y Reproducción es el órgano colegiado adscrito a la Consejería de Salud que vela por el adecuado desarrollo del nuevo derecho, los criterios para su indicación y la información que se proporcione a las parejas candidatas, salvaguardando su intimidad y autonomía. Asimismo, es la responsable de proponer la actualización del listado de enfermedades susceptibles de ser diagnosticadas por Diagnóstico Genético Preimplantatorio. También realiza labores de asesoramiento a los especialistas y, ante la aparición de situaciones con implicaciones éticas, solicitará el correspondiente dictamen de la Comisión Autonómica de Ética e Investigación Sanitarias.
En este órgano colegiado participan representantes de la Administración sanitaria andaluza y de la Comisión Autonómica de Ética e Investigación Sanitarias, así como especialistas en reproducción asistida, embriología humana y genética; colegios de profesionales sanitarios; Agencia de Evaluación de Tecnologías Sanitarias de Andalucía; juristas expertos en la materia, y asociaciones de pacientes y de consumidores y usuarios.
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British couple have entire family using embryo screening
By Sophie Goodchild
A couple have become one of the first in Britain to conceive their entire family through a genetic screening technique. oanne and Adam Henry feared they would never be parents after doctors discovered Joanne had a gene defect. Some of her chromosomes were in the wrong order, causing severe abnormalities in their first child Jasmine. hey were devastated when Jasmine died within minutes of her birth.But experts at Guy's and St Thomas' Hospital in London used a pioneering embryo-testing technique to help conceive their healthy children Amy, five, and Harrison, who is just a few weeks old. Pre-implantation genetic diagnosis is used to assess the health and viability of embryos. Doctors give patients fertility treatment then take a cell from the resulting embryos to test if they are 'normal'. The healthy embryo is implanted back into the mother's womb. Mr and Mrs Henry, of Welwyn Garden City, Hertfordshire, are among only a handful of couples in Britain to have had more than one child using this method. Mr Henry, 38, said his children would not be here without the help of Guy's. We thought we would have to come to terms with not having children but now we have a life with two healthy children in it,' said the company director. Amy was the only one of seven eggs produced by Mrs Henry, 35, which was of good enough quality to implant. This treatment is amazing because without it our children would not be here,' Mr Henry added. 'It was horrible to have a loss like [Jasmine] so when Amy arrived it felt like a real sense of achievement. We even have a photograph of her as an embryo.' About one in 500 people are 'silent' carriers of the same chromosome disorder as Mrs Henry. The condition only becomes obvious when they conceive children. It results in a late miscarriage or a child born with severe disabilities.
Under new laws, doctors can now make more use of PGD to create ' disease free' embryos.
This includes screening embryos to eliminate genes which can increase the chance of developing cancer as well as diseases such as cystic fibrosis and muscular dystrophy. Mr and Mrs Henry were treated by Alison Lashwood at Guy's. Four couples at their fertility unit have become parents to more than one child over the past decade, thanks to PGD.
A fertility nurse told the Evening Standard: 'We only use this procedure if we know the child is at risk of abnormalities.
'It was only because Mrs Henry's first baby was stillborn that we found out she was a carrier of a chromosome rearrangement.
'It is not a solution because a child could still be a carrier, but it spares parents the heartache of repeated miscarriage.'
Some experts have raised concerns about the procedure because doctors have to discard the 'abnormal' embryos.
But Mr Henry said: 'The whole process was very gruelling and we didn't know if we could go through it all again - we had been through so much already, especially with losing Jasmine.
'I'm annoyed people saying, 'Is this ethically correct?' No one is trying to clone a child. We are just two normal people who lost a baby.'
What place do "saviour siblings" have in paediatric transplantation: establishing the role of pre-implantation genetic diagnosis with HLA typing
Background: Not all children in need of a haematopoietic stem cell transplant have a suitable relative or unrelated donor available. Recently, in vitro fertilization (IVF) with pre-implantation genetic diagnosis (PGD) for human leukocyte antigen (HLA) tissue typing has been used to selectively transfer an IVF embryo in order to produce a child who may provide umbilical cord blood for transplantation to an ill sibling. Such children are sometimes called "saviour siblings".
Objective: To examine the published clinical and epidemiological evidence relevant to the use of this technology, with the aim of clarifying those situations where IVF and PGD for HLA-typing should be discussed with parents of an ill child.
Design: A critical analysis of published literature on: comparative studies of umbilical cord blood versus other sources of stem cells for transplantation; comparative studies of matched unrelated donor versus matched related donor transplantation; and the likelihood of finding an unrelated stem cell donor.
Conclusion: IVF and PGD for HLA-typing is only applicable when transplantation is non-urgent and parents are of reproductive age. Discussions regarding this technology may be appropriate where no suitable related or unrelated donor is available for a child requiring a transplant, or where no suitable related donor is available and transplantation is only likely to be entertained with a matched sibling donor. Discussion may also be considered in the management of any child lacking a matched related donor who requires a non-urgent transplant or may require a transplant in the future.
Should baby be risked for sister?
By Vivienne Parry
Radio 4's Inside the Ethics CommitteeCatherine is a little girl condemned by genetic disease to a gruelling regime of treatment.
She could be released from it by a sibling, but the sibling is not yet conceived.
And can one child's health ever be put at risk to save another's?
When Catherine, the first child of Charles and Clara, was born in 2001, she seemed healthy - but not for long.
"She was very listless and would fall asleep in the middle of a feed," said her mother.
"When she was 11 weeks old, she was pretty much pure white, you couldn't even see her lips. We took her into A&E."
Tests revealed that Catherine had virtually no red blood cells.
She was eventually diagnosed with Diamond Blackfan Anaemia (DBA), a genetic disease in which few if any red blood cells are produced by the bone marrow, producing anaemia.
DBA can be treated with day long monthly transfusions.
However, every transfusion adds iron to the body which will cause irreversible organ damage unless removed.
Removal involves giving a drug given as a continuous transfusion through a needle, all through the night, five nights a week.
"Catherine hated it, screaming 'I don't want it, I don't want it'," said Clara.
"She got used to it, but often said: 'Why can't I be normal'."
Risk of early death
DBA carries a one in four chance of early death because of organ damage and an increased risk of childhood cancer.
"Once we saw what her quality of life was and the problems that she might have in the future, we started saying is there something else we can do?", said Clara.
A bone marrow transplant was the only option.
One from an unrelated donor carried up to a 30% risk of death for Catherine, one from a related donor a 5% risk.
Charles and Clare had intended having another baby anyway and hoped that a baby brother or sister would be a tissue match.
With each pregnancy there is the same one in four chance of a match.
But it is possible to use a technique normally used in pre-implantation genetic diagnosis (PGD), in which a cell from the three-day-old embryo is taken to screen out serious genetic disease, for tissue typing, to guarantee that a sibling is a tissue match, before being replaced.
The uncertainty of IVF gives a one in 10 chance of successful pregnancy with such a match.
Spontaneous mutation
There was however a major problem: DBA can be inherited or arise as a spontaneous mutation.
Which sort did Catherine have?
There was no family history of the condition. Tests on Catherine showed she didn't have any of the known mutations that cause DBA, but there are some as yet uknown.
It meant that no-one could test whether another baby had the condition or not.
Not being able to rule out DBA was a major ethical issue.
So Clara and Charles decided to have a baby naturally. But the new baby wasn't a match.
By this time, Catherine was three and the couple were acutely aware that her condition was deteriorating.
She had to have a transplant before she became too sick to survive the procedure.
They decided to go for tissue typing. To do this they needed to have a licence from the Human Fertilisation and Embryology Authority.
But at the time, the HFEA only allowed PGD to be used for tissue typing where a disease could be screened out. This was not possible in Catherine's case.
So the couple went to the US, where it was permitted. But two attempts failed.
They were psyching themselves up for a third attempt, when they read about a UK couple in the same situation as themselves, who had been given a licence by the HFEA following a judicial review.
They decided to try for a 'saviour sibling' using PGD.
Devastating blow
The procedure of taking stem cells for a bone marrow transplant would not harm Catherine's sibling, because they could be obtained from cord blood at birth.
When baby sister, McKenzie was born, not enough stem cells could be collected for a transplant.
It was a devastating blow - but at least she was free from DBA.
"Every picture I took of them together had added meaning because Catherine was looking at her lifeline," said Clara.
A much more invasive collection of bone marrow from McKenzie involving 90 minutes of general anaesthesia was now required.
There is no benefit to the donor, and McKenzie was not able to provide consent.
The chances of success for Catherine were getting less as time went on, but the younger McKenzie was, the greater the risks of anaesthesia for her.
Competing interests
Here the ethical issues are the competing 'best interests' of the sisters.
There is also the issue that the donation will only cure Catherine's symptoms, not rid her of the condition.
There is a good chance it could fail. How would McKenzie feel later knowing that her donation failed to save her sister?
And should Catherine's kidneys fail, then once again, McKenzie would be the first choice of donor.
The Clinical Ethics Committee decided that the bone marrow transplant should go ahead. It took place 18 months ago.
It was a success and Catherine continues to do well.
Baby to be born free of breast cancer after embryo screening
