A pregnancy following PGD for X-linked autosomal dominant Incontinentia Pigmenti (Bloch-Sulzberger syndrome)

Incontinentia Pigmenti (Bloch-Sulzberger syndrome) is a rare multisystem, e ctodermal disorder associated with dermatological, dental and ocular featur es, and in <10% of cases, severe neurological deficit. Pedigree review sugg ests X-Linked dominance with lethality in affected males. Presentation in f emale carriers is variable, Following genetic counselling, a mildly affecte d female carrier diagnosed in infancy with a de novo mutation was referred for preimplantation sexing, unusually selecting for male gender, with an ac ceptance of either normality or early miscarriage in an affected male. Foll owing standard in-vitro fertilization and embryo biopsy, fluorescence in si tu hybridization (FISH) unambiguously identified two male and two female em bryos, A single 8-cell, grade 4 male embryo was replaced, A positive pregna ncy test was reported 2 weeks after embryo transfer, although ultrasonograp hy failed to demonstrate a viable pregnancy. Post abortive fetal tissue kar yotyping diagnosed a male fetus with trisomy 16, This is an unusual report of preimplantation genetic diagnosis (PGD) being used for selection of male s in an X-linked autosomal dominant disorder and demonstrates the value of PGD where amniocentesis or chorion villus sampling followed by abortion is not acceptable to the patient. This ease also demonstrates the importance o f follow-up prenatal diagnosis.