Chien Yin-Hsiu, Chiang Shu-Chuan, Huang Aichu, Hwu Wuh-Liang
Department of Medical Genetics, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
Early Hum Dev. 2005 Jun;81(6):529-33. doi: 10.1016/j.earlhumdev.2004.11.005. Epub 2004 Dec 19.
Measurement of methionine levels in dried blood spots has been one of the items of neonatal screening in Taiwan for more than 20 years. In 1,701,591 newborns, 17 cases of hypermethioninemia were detected, but among them only one had homocystinuria. More than half of the 16 cases of isolated hypermethioninemia had mutations in the MAT1A gene, and four of the eight MAT1A mutations identified in this study have not been reported before. Therefore methionine adenosyltransferase deficiency is the most prevalent cause of isolated hypermethioninemia in Taiwanese. Although most of the patients with isolated hypermethioninemia were put on diet in this study, their IQ scores were not related to either the initial or follow-up plasma methionine levels. Because both the etiology and the natural history of isolated hypermethioninemia haven't been clearly resolved, the impact of this condition on screening programs where homocystinuria is rare should be carefully evaluated.
二十多年来，测定干血斑中的蛋氨酸水平一直是台湾新生儿筛查项目之一。在1701591名新生儿中，检测出17例高蛋氨酸血症，但其中只有1例患有同型胱氨酸尿症。16例孤立性高蛋氨酸血症患者中，超过半数在MAT1A基因存在突变，本研究中鉴定出的8个MAT1A突变中有4个此前未曾报道过。因此，蛋氨酸腺苷转移酶缺乏是台湾孤立性高蛋氨酸血症最常见的病因。尽管本研究中大多数孤立性高蛋氨酸血症患者接受了饮食治疗，但其智商得分与初始或随访时的血浆蛋氨酸水平均无关联。由于孤立性高蛋氨酸血症的病因和自然史尚未明确解决，在同型胱氨酸尿症罕见的筛查项目中，应仔细评估这种情况的影响。
