De novo deletion of chromosome 18q in a baby with harlequin ichthyosis.

[harlequin ichthyosis]

Harlequin ichthyosis , (MIM 242500 ), is a rare , autosomal recessive skin disorder due to an inborn error of epidermal keratinization . The gene for this condition has not been localized . We present a case of HI in which there was a de novo deletion of chromosome 18 q : the karyotype was 46 , XY , del (18 )(q 21 .3 ). We postulate that the gene for HI may lie at , or distal to 18 q 21 .3 and that the deletion observed in this case may have unmasked this autosomal recessive disorder .