胱硫醚-β-合酶缺乏症：通过同型半胱氨酸与半胱氨酸及叶酸的比率检测杂合子。

Cystathionine-beta-synthase deficiency: detection of heterozygotes by the ratios of homocysteine to cysteine and folate.

作者信息

Boddie A M, Steen M T, Sullivan K M, Pasquali M, Dembure P P, Coates R J, Elsas L J

机构信息

Division of Medical Genetics, Department of Pediatrics, Emory University School of Medicine, Atlanta, GA 30302, USA.

出版信息

Metabolism. 1998 Feb;47(2):207-11. doi: 10.1016/s0026-0495(98)90222-0.

DOI:10.1016/s0026-0495(98)90222-0

PMID:9472972

Abstract

Elevated total plasma homocysteine (tHcy) is recognized as an independent risk factor for occlusive vascular disease. However, it is not known how much of the observed hyperhomocysteinemia in patients with vascular disease is due to heterozygosity for cystathionine-beta-synthase (CbetaS) deficiency, because a clinically useful screening method is unavailable. To determine this, parents of children who are homozygous for CbetaS deficiency (affected with homocystinuria) and a control population were compared for tHcy, total plasma cysteine (tCys), plasma folate, and plasma vitamin B12. The group of obligate heterozygotes had increased tHcy (P < or = .01), decreased tCys (P < or = .01), and decreased plasma folate (P < or = .01). The calculated ratios of tHcy/tCys (P = .01) and tHcy/plasma folate (P = .003) were the best metabolic discriminants for genotype. These ratios are likely to prove useful in heterozygote screening for CPS deficiency and in the development of rational treatment strategies for patients with increased tHcy.

摘要

血浆总同型半胱氨酸（tHcy）升高被认为是闭塞性血管疾病的独立危险因素。然而，尚不清楚血管疾病患者中观察到的高同型半胱氨酸血症有多少是由于胱硫醚-β-合酶（CbetaS）缺乏的杂合性所致，因为目前尚无临床可用的筛查方法。为了确定这一点，对CbetaS缺乏纯合子（患同型胱氨酸尿症）儿童的父母和对照组人群的tHcy、血浆总半胱氨酸（tCys）、血浆叶酸和血浆维生素B12进行了比较。 obligate杂合子组的tHcy升高（P≤0.01）、tCys降低（P≤0.01）、血浆叶酸降低（P≤0.01）。计算得出的tHcy/tCys比值（P = 0.01）和tHcy/血浆叶酸比值（P = 0.003）是基因型最佳的代谢判别指标。这些比值可能在CPS缺乏的杂合子筛查以及tHcy升高患者合理治疗策略的制定中被证明是有用的。