Further delineation of the 3-M syndrome with review of the literature

The 3-M syndrome is a clinically recognizable disorder characterized by prenatal and postnatal growth retardation and a spectrum of consistent minor anomalies. Intelligence seems normal. Inheritance is probably autosomal recessive, with possible expression of the mutant gene in the heterozygote. Three sibs with the 3-M syndrome are reported, together with an extensive review of the pertinent literature.     

Hemihydranencephaly with Favourable Outcome

The authors report a girl with left-sided hemiparesis and unilateral hydranencephaly of the opposite side. Her psychomotor development has been far better than expected--she is only mildly delayed. Hemihydranencephaly is a rare anomaly: only five other cases are reported in the literature, three of whom were also mildly delayed. The fourth patient had multiple congenital defects combined with the hemihydranencephaly and was severely retarded, and no data on the fifth patient were provided. It may be that the prognosis for hemihydranencephaly is better than for most other destructive encephalopathies, which generally carry a poor prognosis for psychomotor development.     

Familial neurofibromatosis type 1 associated with an overgrowth syndrome resembling Weaver syndrome.

The simultaneous occurrence of familial neurofibromatosis type 1 (NF1) and an overgrowth syndrome resembling Weaver syndrome was observed in two related cases (a mother and her son). NF1 was confirmed by molecular genetic analysis showing a large deletion at 17q11.2, encompassing the entire NF1 gene. The other symptoms in the two cases were similar to the features reported in Weaver syndrome. Although the combination of NF1 and an overgrowth syndrome resembling Weaver syndrome in this family may be fortuitous, we favour the hypothesis that the deletion of the entire gene has caused this combined phenotype. Possible pathogenetic mechanisms are discussed. The observation suggests a relation between NF1 with an extraordinarily large gene deletion and a Weaver(-like) syndrome. This warrants investigation for deletions in the 17q11.2 region in Weaver(-like) syndrome patients.