Are Melnick-Needles syndrome and oto-palato-digital syndrome type II allelic? Observations in a four-generation kindred.

Melnick-Needles syndrome (MNS) is a female-limited skeletal dysplasia inherited in a X-linked dominant pattern. Males born to women with MNS may exhibit lethal multiple congenital anomalies, but recurrence of this phenotype within one family has not been reported. Males with oto-palato-digital syndrome type II (OPD II) also demonstrate a multiple congenital anomalies phenotype that includes skeletal dysplasia but the maternal phenotype includes only mild craniofacial anomalies. These two syndromes have been suggested as being allelic despite differences in the described maternal phenotypes. We present a four-generation kindred in which four males had a consistent multiple congenital anomalies phenotype. The females in this family have skeletal changes characteristic of MNS but have only mild craniofacial anomalies and also deafness attributable to ossicular deformity, traits more commonly found in OPD II. The expression of manifestations of MNS and OPD II in males and females in this kindred further suggest that these syndromes are allelic.