Are heterocygotes for classical homocystinuria at risk of vitamin B-12 and folic acid deficiency?

Objectives/design: Comparative cross-sectional study to assess homocysteine and vitamin status in carriers of CBS gene mutations

Newborn Population Screening for Classic Homocystinuria by Determination of Total Homocysteine from Guthrie Cards

Objective To allow early recognition of cystathionine beta-synthase by newborn screening

A Common Mutation in the CBS Gene Explains a High Incidence of Homocystinuria in the Qatari Population

We report the results of a study carried out to delineate genetic and epidemiological aspects of homocystinuria in the Qatari population. Sixty-four patients with homocystinuria (37 males, 27 females, age 1 to 29 years) from 31 nuclear families were ascertained over a period of more than four years. The incidence of homocystinuria in Qatar was calculated to be >= 1:3000, the highest in the world known so far. All patients in whom data were available were vitamin B-6-nonresponsive. Molecular studies were performed in all patients. All 53 patients from tribe M and all three patients from tribe K were homozygous for the mutation c.1006C>T (p.R336C) in the CBS gene, with an additional seven patients resulting from mixed marriages between tribe M and tribe K. A single patient from tribe S was homozygous for mutation c.700G>A (p.D234N) in the CBS gene. Both mutations have been previously reported but involve hypermutable CpG dinculeotides and may be recurrent mutations in the Qatari population. The results of this study illustrate a strong founder effect causing a high prevalence of an autosomal recessive disease in a highly consanguineous Arabian population. Molecular neonatal screening may be suitable for early detection of homocystinuria in this population. (C) 2006 Wiley-Liss, Inc