Delineation of the interstitial 6q25 microdeletion syndrome: refinement of the critical causative region.

Interstitial deletions of the long arm of chromosome 6 are rare. Clinically, this is a recognizable microdeletion syndrome associated with intellectual disability (ID), acquired microcephaly, typical dysmorphic features, structural anomalies of the brain, and nonspecific multiple organ anomalies. Most of the reported cases have cytogenetically visible interstitial deletions or subtelomeric microdeletions. We report on a boy with global developmental delay, distinct dysmorphic features, dysgenesis of the corpus callosum, limb anomalies, and genital hypoplasia who has a small interstitial deletion of the long arm of chromosome 6 detected by comparative genomic hybridization (CGH). The deleted region spans around 1 Mb of DNA and contains only two coding genes, ARID1B and ZDHHC14. To the best of our knowledge, this case represents the typical phenotype with the smallest deletion reported so far. We discuss the possible role of these genes in the phenotypic manifestations.

Transient Motor Asymmetry Among Infants With Congenital Torticollis-Description, Characterization, and Results of Follow-Up.

AIM: The purpose of this study was to assess the prevalence of transient functional motor asymmetry in infants with congenital postural torticollis. METHODS: This was a retrospective review of the medical records of infants with postural torticollis. We analyzed epidemiological, obstetric, perinatal data, physical therapy, physician assessments, and clinical follow-up for two years after diagnosis. RESULTS: Of 173 children, 44 (25.4%, 95% confidence interval = 19.5 to 32.4) demonstrated functional asymmetry. Demographic and obstetrical data did not differ between the asymmetry/nonasymmetry groups. Delayed motor development (P = 0.01) and plagiocephaly (P = 0.032) were more common in infants with motor asymmetry. No difference was observed in the frequency of referral for further neurological diagnosis between the group with functional asymmetry and that without asymmetry. Among the 44 patients with functional asymmetry, 78% depicted no evidence of torticollis by age two years, and the motor asymmetry had disappeared in 82%. CONCLUSION: Benign, transient functional motor asymmetry occurred in a quarter of infants with congenital postural torticollis. Transient motor delay was also significantly more common in the asymmetry group. In most instances, motor asymmetry and motor delay disappeared by age two years. Plagiocephaly was more common in the asymmetry group. Clinician awareness of this transient asymmetry may have avoided unnecessary diagnostic tests in these infants.