Megarbane et al. (2004) described a Lebanese brother and sister, born of first-cousin parents, with short stature, microcephaly, ptosis, small, dysplastic, low-s...
Megarbane et al. (2004) described a Lebanese brother and sister, born of first-cousin parents, with short stature, microcephaly, ptosis, small, dysplastic, low-set ears, short neck, and pectus malformations (pectus carinatum superiorly and excavatum inferiorly). The boy also had a high-arched palate, a small perimembranous ventricular septal defect, absence of fusion of the posterior hemi-arches of C7, and a fusion between L5 and S1 with a sagittal-cleft vertebral body of L5. The girl had a cleft lip and palate and bilateral cervical ribs. The parents had 3 unaffected daughters. Family history revealed that they had 2 other children, a boy and girl, with features similar to those of the affected sibs. The girl died at age 6 of cardiac arrest after acute renal failure following treatment for an episode of seizures. The boy was born with a cleft lip and palate and died at 40 days of age. Because of phenotypic overlap with Noonan syndrome (163950), Megarbane et al. (2004) searched for mutations in exons 2, 3, 4, 7, 8, 12, and 13 of the PTPN11 gene (176876), but found none.
Megarbane et al. (2004) suggested autosomal recessive inheritance of this disorder because of parental consanguinity and affected sibs of both sexes.