First baby born free of genetic disorder carried by parents

Child is first reported case in world free of parents’ mucolipidosis gene after PGD process

An Irish newborn has become the first reported case in the world of a baby born free of an extremely rare fatal condition despite both of her parents carrying the gene that causes the disorder.

Megan O’Connor’s parents John and Emma are both carriers of a gene which leads to the metabolic disorder mucolipidosis, but thanks to pre-implantation genetic diagnosis (PGD), Megan was born free of the gene.

According to Dr John Waterstone of the Cork Fertility Clinic which provided the PGD service, Megan, who was born on March 24th at Cork University Maternity Hospital, is doing well.

“It is the first reported incidence in the world of successful PGD with karyomapping in the case of mucolipidosis, which is a life-limiting condition,” said Dr Waterstone.


Dr Waterstone explained that karyomapping is a new technique that has transformed the field of PGD due to its rapid and robust method of detecting a wide range of genetic diseases in embryos.

“The baby’s parents are both carriers of a mutation affecting the mucolipidosis gene, and without PGD they had a one-in-four chance of having a baby affected by the condition.”

Metabolic disorder

Mucolipidosis is a rare inherited metabolic disorder where growth usually stops before a child is aged two. Most people who are born with mucolipidosis do not survive past early childhood.

Anne Lawlor, information and development officer with the Genetic and Rare Disorders Organisation (GRDO), said they had been following the development of PGD in Ireland closely.

“An estimated 300,000 Irish people will be affected by a rare disease in their lifetime, 80 per cent of which are genetic in origin; progress in medical research is resulting in more options becoming available.

“And this progress is allowing those with genetic conditions in their families to make informed decisions on future healthcare options, both for themselves and for their families,” she said.

Cystic fibrosis

Last July, Cork couple Patrick Mullane and Lisa Cooke became the first couple to have a baby born as a result of PGD carried out in Ireland when their daughter, Bridget, was born free of cystic fibrosis.

They had also availed of PGD at the Cork Fertility Centre to prevent Bridget from inheriting cystic fibrosis, and the eight-month-old is now thriving.

Dr Waterstone said almost 70 per cent of the couples who have had an embryo transfer after PGD at the Cork Fertility Clinic have become pregnant, and this was a very promising success rate.

“We hope that these couples will be the first of many to avoid passing on inherited conditions as a result of PGD,” said Dr Waterstone.

Health professionals say genetic screening technology can play a vital role in preventing miscarriages and the inheritance of debilitating genetic conditions.

Assisted human reproduction is not regulated in Ireland, although Minister for Health Leo Varadkar recently announced plans to draw up legislation for the area.

Barry Roche

Barry Roche

Barry Roche is Southern Correspondent of The Irish Times