FAP Patients Have a Moderate Chance of Having Unaffected Children, Study Suggests

Patients with familial amyloid polyneuropathy (FAP) appear to have intact reproductive capacity, even when they have undergone a liver transplant or receive treatment with Vyndaqel (tafamidis), a retrospective study suggests.

Researchers from the University of Porto, in Portugal, reached this conclusion after studying FAP patients carrying the V30M mutation who underwent a preimplantation genetic diagnosis to have a child not affected by the disease.

Because about half of all attempts using this technique were successful, with no stillbirths or early infant deaths, the data also support the feasibility of preimplantation diagnostics to avoid passing on the disease to future children, researchers said in the report, which was published in the journal Reproductive BioMedicine Online.

Using preimplantation genetic diagnosis — the genetic profiling of embryos used in combination with in vitro fertilization — patients with FAP have a chance of having a child that is unaffected by their disease.

The study, “Clinical outcomes after preimplantation genetic diagnosis of patients with Corino de Andrade disease (familial amyloid polyneuropathy),” included 28 FAP patients, of which 17 were men. Among them, two women and five men underwent the procedure after a liver transplant.

Researchers compared men and women with the disease and found that there were few differences between them in terms of their ability to conceive a child using the technique.

There were also no differences between male and female patients in fertilization rates, number of transferred embryos, or rates of implantation, miscarriage, or live birth deliveries.

Embryos from female patients were of lower quality when assessed at day three, and FAP women had a lower rate of pregnancies compared to women who had a male partner with FAP.

Nearly half — 48 percent — of all embryo transfer attempts were successful with no so-called ectopic pregnancies, in which the fetus starts growing outside the uterus. There were no stillbirths in the study, and no infants died soon after birth.

Interestingly, FAP women tended to get girls more often — six out eight babies born to FAP women were girls — while men with FAP had boys in seven out of 10 cases. Researchers believed that in the case of men, this might have been caused by the gathering of sperm directly from the testicles in some.

There were only three preterm deliveries in the study and most children had a normal birth weight.

The study suggests that men and women with FAP have equal chances of having a child using preimplantation diagnosis. Moreover, the chances are relatively good that such an attempt will succeed, giving rise to a healthy child.