Cystathionine synthase T833C/844ins68 Polymorphism: A family-based study on down syndromes children

Yıl 2011, Cilt: 2 Sayı: 2, 54 - 56, 01.12.2011

Aysegul Turkyılmaz Selda Sımsek Diclehan Oral Selahattin Tekeş Hilmi Isı

Öz

Cystathionine β-synthase (CBS) mediates conversion of homocysteine to cystathionine and deficiency in
enzyme activity may be lead to hyperhomocysteinemia/homocystinuria, which are often associated with
Down Syndrome (DS). A large number of polymorphisms have been reported in the CBS gene, some of which
impair its activity and among these, a T833C polymorphism in cis with a 68 bp insertion at 844 in the
exon 8 is found to be associated with mild hyperhomocysteinemia in different ethnic groups. Our aim in the
present study is to investigate the association between T833C/844ins68 polymorphism and DS.
Methods: Fifty-seven DS cases parents (mothers) were recruited after psychometric evaluation.
Peripheral blood was collected after obtaining informed written consent. The T833C/844ins68
polymorphism was investigated by PCR amplification of genomic DNA
Results: After PCR Analysis 15 samples were found to have +/- genotype while 42 samples were found
to have -/- genotype for CBS 844ins68 polymorphisms.
Conclusion: This is the first molecular genetic study of CBS gene dealing with T833C/844ins68 double
mutation in DS subjects in our region. The next step is to extended number of cases and to use more controls
for T833C/844INS68 polymorphism.

Anahtar Kelimeler

Down Syndrome, CBS gene, T833C/844ins68 polymorphism

Kaynakça

• Scala I. Granese B. Sellitto M. et al. Analysis of seven maternal polymorphisms of genes involved in homocysteine/folate metabolism and risk of Down syndrome offspring Genetics IN Medicine July 2006; 8 :7, 406-16.
• Dutta S. Sinha S. Chattopadhyay A.et al. Cystathionine b - synthase T833C/844INS68 polymorphism: a family- based study on mentally retarded children Behavioral and Brain Functions 2005, 1: 25, 2-6.
• Romano M. Marcucci R. Buratti E. et al. Regulation of 3- Splice Site Selection in the 844ins68 Polymorphism of the Cystathionine b-Synthase Gene. . J. BIOL. CHEM. November 2002 ; 277: 15, 43821–29.
• Franco R. Maffei F. Lourenço D. et al The frequency of 844ins68 mutation in the cystathionine b-synthase gene is not increased in patients with venous thrombosis Haematologica 1998; 83,1006-8.