DNA-based prenatal exclusion of harlequin ichthyosis.

Harlequin ichthyosis (HI) is a severe and usually fatal congenital ichthyosis with an autosomal recessive inheritance pattern. Until the identification of ABCA12 as the causative gene, prenatal diagnosis (PND) for HI had been performed by electronmicroscopic observation of fetal skin biopsy samples. We report herein a case of DNA-based prenatal exclusion of HI. We performed PND by direct sequence analysis and restriction enzyme digestion analysis using fetal genomic DNA from amniotic fluid cells at 16 weeks' gestation. This study demonstrates the efficacy of early DNA-based exclusion of HI.