Congenital Disorders of Glycosylation (CDG) are scarcely reported from Latin America. We here report on a Mexican mestizo with a multi-systemic syndrome including neurological involvement and a type I transferrin (Tf) isoelectric focusing (IEF) pattern. Clinical exome sequencing (CES) showed known compound missense variants in PMM2 c.422G > A (p.R141H) and c.395 T > C (p.I132T), coding for the phosphomanomutase 2 (PMM2). PMM2 catalyzes the conversion of mannose-6-P to mannose-1-P required for the synthesis of GDP-Man and Dol-P-Man, donor substrates for glycosylation reactions. This is the third reported Mexican CDG patient and the first with PMM2-CDG. PMM2 has been recently identified as one of the top 10 genes carrying pathogenic variants in a Mexican population cohort.

拉丁美洲很少报道先天性糖基化疾病（CDG）。我们在这里报道了一种具有多种系统综合症的墨西哥混血儿，包括神经系统疾病和I型转铁蛋白（Tf）等电聚焦（IEF）模式。临床外显子组测序（CES）显示了PMM2 c.422G> A（p.R141H）和c.395 T> C（p.I132T）中已知的化合物错义变体，编码磷酸甘露糖异位酶2（PMM2）。PMM2催化甘露糖6-P转化为甘露糖合成反应的供体底物GDP-Man和Dol-P-Man合成所需的甘露糖1-P转化。这是第三例墨西哥CDG患者，第一例患有PMM2-CDG。最近，PMM2被确定为墨西哥人口队列中携带致病性变异的十大基因之一。