Further evidence for autosomal dominant inheritance and ectodermal abnormalities in Kabuki syndrome.

Most cases with Kabuki syndrome (KS) were reported sporadically. Recently, a few familial cases of KS were reported. This report provides further evidence that the KS is inherited as a dominant trait with variable expressivity. The proposita is an 18-month-old girl with facial findings characteristic of Kabuki syndrome, prominent fingertip-pads, a midsagittal cleft of vertebral body D4, hypotonia, and psychomotor retardation. Her mother had a similar facial appearance, prominent, cup-shaped ears, an abnormal dentition, early breast development, and low-normal intelligence. Because mother and daughter both had evident Kabuki syndrome, we conclude that KS in this family is inherited as a dominant trait. Further family history supports this finding. Microscopic examination of the hair of the proposita shows abnormalities consisting of trichorrhexis nodosa, twisting of the hairshafts, and irregularity of the diameter of the hair, as was described recently in a patient with KS. This could be another occasional finding in this syndrome, but further studies are required. The presence of abnormal hair, nails, and the commonly described tooth abnormalities in KS further suggest ectodermal involvement in this syndrome.