Elsaid Mahmoud F, Bener Abdulbari, Lindner Martin, Alzyoud Mahmoud, Shahbek Noora, Abdelrahman Mohammed O, Abdoh Ghassan, Bessisso Mohammed S, Zschocke Johannes, Hoffmann Georg F
Department of Pediatrics Neurology Unit, Hamad General Hospital, Hamad Medical Corporation, Qatar, and Department of Evidence for Population Health Unit, School of Epidemiology and Health Sciences, The University of Manchester, UK.
Mol Genet Metab. 2007 Sep-Oct;92(1-2):100-3. doi: 10.1016/j.ymgme.2007.06.010. Epub 2007 Aug 7.
OBJECTIVES/DESIGN: Comparative cross-sectional study to assess homocysteine and vitamin status in carriers of CBS gene mutations.
Subjects included 34 parents (13 males, 21 females, age 27-59 years) of 30 patients with classical homocystinuria due to homozygous cystathionine beta-synthase deficiency. Control subjects were matched for gender and age (13 males, 21 females, age 25-59 years). All subjects were of Qatari origin, had normal liver and renal function tests and had not taken drugs or vitamin supplements prior to the study. The concentrations of homocysteine, folic acid and vitamins B6 and B12 in blood were determined after an overnight fast.
Heterozygous carriers had significantly increased fasting levels of homocysteine compared to controls (9.1 vs. 8.1 micromol/l, P=0.012). Both folic acid (328 vs. 478 pmol/l, P=0.002) and vitamin B12 concentrations (232 vs. 287 pmol/l, P=0.013) were reduced whilst there was no significant difference in vitamin B6 levels between the two groups (5.8 vs. 6.44 microg/l).
Increased homocysteine concentrations in CBS gene mutation carriers are associated with reduced concentrations of folic acid and vitamin B12 in blood. In view of the adverse effects of mild hyperhomocysteinemia, routine testing of vitamin status in parents of homocystinuria patients may be warranted. The causal relationship and pathophysiological consequences are uncertain; it is likely that CBS gene mutation carriers need higher doses of dietary vitamins.
目的/设计：一项比较性横断面研究，旨在评估胱硫醚β-合酶（CBS）基因突变携带者的同型半胱氨酸和维生素状态。
研究对象包括30例因纯合子胱硫醚β-合酶缺乏导致典型同型胱氨酸尿症患者的34名父母（13名男性，21名女性，年龄27 - 59岁）。对照组在性别和年龄上进行匹配（13名男性，21名女性，年龄25 - 59岁）。所有研究对象均为卡塔尔裔，肝功能和肾功能检查正常，且在研究前未服用药物或维生素补充剂。空腹过夜后测定血液中的同型半胱氨酸、叶酸以及维生素B6和B12的浓度。
与对照组相比，杂合子携带者的空腹同型半胱氨酸水平显著升高（9.1对8.1微摩尔/升，P = 0.012）。叶酸（328对478皮摩尔/升，P = 0.002）和维生素B12浓度（232对287皮摩尔/升，P = 0.013）均降低，而两组间维生素B6水平无显著差异（5.8对6.44微克/升）。
CBS基因突变携带者中同型半胱氨酸浓度升高与血液中叶酸和维生素B12浓度降低有关。鉴于轻度高同型半胱氨酸血症的不良影响，对同型胱氨酸尿症患者的父母进行维生素状态的常规检测可能是必要的。因果关系和病理生理后果尚不确定；CBS基因突变携带者可能需要更高剂量的膳食维生素。
