Danish sperm donor passed neurofibromatosis on to five children.

Danish health authorities are expected to restrict regulations regarding sperm donation after a donor was found to have passed on the genetic disease neurofibromatosis to at least five children he fathered.

The donor donated his sperm to the Copenhagen based sperm bank Nordisk Cryobank, which did not screen for the genetic disorder. The sperm were subsequently used by several different fertility clinics. According to the Danish broadcasting corporation (DR), the man has fathered 43 children in 14 different in vitro fertilisation (IVF) clinics.

The clinics are located not only in Denmark but also in Sweden, Norway, and several other countries inside and outside Europe. Nordisk Cryobank said that five of the children have been affected by neurofibromatosis.

Peter Bower, director of Nordisk Cryobank, told DR that the clinic continued to use the sperm after cases of neurofibromatosis had been discovered because doctors did not believe that the donor was responsible for passing on the condition. Confidentiality rules meant that Bower could not comment on when and where the affected children had been born. However, Swedish radio reported that 18 of the 43 children were born in Sweden and Norway.

The fact that Nordisk Cryobank had not immediately withdrawn sperm from the donor when cases of neurofibromatosis were reported has been criticised by Anne-Marie Vangsted, head of the Danish Health and Medicines Authority. Parents of children fathered by the donor are considering legal action.

Denmark has liberal laws regarding artificial insemination and sperm donations. Many women from other countries with more restrictive regulations, such as Sweden, come to Denmark for artificial insemination. Denmark currently has a limit of 25 children per sperm donor.

Starting from October this year, however, new regulations from the Health and Medicines Authority state that each sperm donor may not father more than 12 children. Further, Danish sperm banks will immediately have to withdraw sperm if any suspicions regarding genetic diseases should come to their knowledge.

Neurofibromatosis is a genetic autosomal disorder. That means that if one of the parents carries the mutation, the child has a 50:50 chance of developing the disorder, depending on whether or not he or she inherits the faulty gene. The disease is characterised by tumour growth in nerve tissue. Neurofibromatosis has no cure, and it can manifest through several symptoms, such as bone deformity, hearing loss, learning disabilities, and scoliosis. Some patients develop malignant tumours.

The most common form of the disease is called neurofibromatosis type-1 (NF-1) and is also known as Von Recklinghausen’s disease. NF-1 accounts for about 90% of all cases of neurofibromatosis, among them the children of the Danish sperm donor. It is caused by a mutation in the gene neurofibromin 1 on chromosome 17. About one in 4000 individuals carry the mutation. In some cases, however, the mutation does not come from one of the parents but has developed spontaneously in the affected individual.