Sibs with anencephaly, anophthalmia, clefts, omphalocele, and polydactyly:Hydrolethalus or acrocallosal syndrome?

Major characteristics of the acrocallosal syndrome include severe mental re tardation, agenesis or hypoplasia of the corpus callosum, and polydactyly o f fingers and toes, In the past few years, anencephaly has also been noted, together with other midline defects. We report on a nonconsanguineous, Nor wegian couple with a history of two pregnancies with a male and a female fe tus, respectively, with anencephaly, median cleft lip and palate, omphaloce le, and preaxial polydactyly, suggesting the diagnosis of the acrocallosal syndrome. Both fetuses also lacked eyes and nose, a finding not previously reported in the acrocallosal syndrome, Microphthalmia has been reported in the hydrolethalus syndrome, which may be caused by mutations in the same ge ne as the acrocallosal syndrome. The present report adds support to the hyp othesis that the acrocallosal and hydrolethalus syndromes may be allelic co nditions, The family history is consistent with autosomal recessive inherit ance. (C) 2000 Wiley Liss, Inc.