Benign familial macrocephaly in a mother-son pair.

Macrocephaly can be found isolated or associated with other anomalies as a part of specific syndrome. Benign Familial Macrocephaly (BFM) is a primary macrocephaly and autosomal dominant and multifactorial inheritances had been proposed. Cole and Hughes (5), described clinically seven patients. We report two BFM cases, a boy and his mother. The male propositus showed macrocephaly with dolicocephaly shape, frontal bossing, narrowing biparietal and a square-shaped face. Neurological examination was normal. He had two computed tomography (CT) scans of the skull, one at 7 months of age showing extracerebral fluid collection in the anterior convexity and increased interhemispheric subarachnoid space and a second normal CT scan at 3 years of age. The mother showed macrocephaly with dolycocephaly shape and dished-out mid-face. This family exhibited the full clinical spectrum of BFM, with an autosomal dominant inheritance.

A missense mutation, p.V132G, in the X-linked spermine synthase gene (SMS) causes Snyder-Robinson syndrome.

Snyder-Robinson syndrome (SRS, OMIM 309583) is a rare X-linked syndrome characterized by mental retardation, marfanoid habitus, skeletal defects, osteoporosis, and facial asymmetry. Linkage analysis localized the related gene to Xp21.3-p22.12, and a G-to-A transition at point +5 of intron 4 of the spermine synthase gene, which caused truncation of the SMS protein and loss of enzyme activity, was identified in the original family. Here we describe another family with Snyder-Robinson syndrome in two Mexican brothers and a novel mutation (c.496T>G) in the exon 5 of the SMS gene confirming its involvement in this rare X-linked mental retardation syndrome.

Metaphyseal chondrodysplasia, upper limb mesomelia and normal height (mesomelic dysplasia camera type): second report in a Mexican patient.

Mesomelic dysplasias (MD) are a group of skeletal disorders with exclusive or predominant shortness of the middle segment of the limbs, with or without involvement of the hands/feet or other body parts. Short stature is a usual consequence due to involvement of the lower limbs. In 2003, Camera and Camera reported an unusual upper limb MD with normal stature and radiological evidence of long bone metaphyseal dysplasia. Here, we describe a Mexican patient showing a similar clinical and radiological phenotype, in addition to esophageal atresia, palpebral ptosis and slight lower limb asymmetry. This represents the second case reported in the literature, corroborating the existence of this rare entity.

Schilbach-Rott syndrome in a third family: further delineation of an autosomal dominant trait.

We describe a father-son Mexican pair with typical features of Schilbach-Rott syndrome (SRS): ocular hypotelorism, cleft palate, hypospadias (only in the child), and microcephaly. This observation documents for the first time a male to male transmission and therefore confirms that the SRS is inherited as an autosomal dominant trait with variable expressivity.