Zerkaoui M, Ratbi I, Castellotti B, Gellera C, Lyahyai J, Kriouile Y, Sefiani A
Centre de Génomique Humaine, Faculté de Médecine et de Pharmacie, Université Mohammed V, Rabat, Morocco.
Département de Génétique Médical, Institut National d'Hygiène, Rabat, Morocco.
BMC Pediatr. 2015 Nov 13;15:182. doi: 10.1186/s12887-015-0490-9.
Krabbe disease (KD) or globoid cell leukodystrophy is an autosomal recessive lysosomal disorder, which affects metabolic and neurologic systems. This pathology has different forms. Infantile onset is about 85% to 90% of individuals with Krabbe disease. Disorder's onset is characterized, in early childhood, by hyperirritability, psychomotor deterioration associated to episodes of fever. To date, all reported cases have been attributed to mutations in galactosylceramidase gene (GALC gene) that encodes an enzyme which degrades galactosyl-sphingolipids (galactosylceramide, psychosine), essential in myelin production. A child compounded with two new mutations in the GALC gene was detected.
An eleven month old male child of Moroccan origin presented to our genetic consultation with severe symptoms that included hypotonia, fever, vision loss and feeding difficulties. He was suffering from the 4th month of life. Krabbe disease was suspected. Galactocerebrosidase deficiency was confirmed by biochemical analysis. DNA sequencing revealed a novel heterozygous compound mutation in GALC gene. The child was compounded with two mutations c.860G > A; p.Cys287Tyr and c.1622G > A; p.Trp541*.
These new mutations could affect GALC structure and therefore its function. The identification of these mutations and their associated phenotypes are important to predict the prognosis and to confer to families an adequate genetic counseling.
克拉伯病(KD)或球状细胞脑白质营养不良是一种常染色体隐性溶酶体疾病,会影响代谢和神经系统。这种病症有不同的形式。婴儿期发病的患者约占克拉伯病患者的85%至90%。该病症在幼儿期的发病特征为易激惹,以及与发热发作相关的精神运动发育迟缓。迄今为止,所有报告的病例都归因于半乳糖神经酰胺酶基因(GALC基因)的突变,该基因编码一种降解半乳糖鞘脂(半乳糖神经酰胺、半乳糖脑苷脂)的酶,而半乳糖鞘脂在髓鞘生成中至关重要。检测到一名患有GALC基因两个新突变的儿童。
一名11个月大的摩洛哥裔男童因出现严重症状前来我们的遗传咨询门诊,这些症状包括肌张力减退、发热、视力丧失和喂养困难。他从4个月大时就开始患病。怀疑是克拉伯病。通过生化分析证实了半乳糖脑苷脂酶缺乏。DNA测序显示GALC基因存在一种新的杂合复合突变。该儿童存在两种突变,即c.860G>A;p.Cys287Tyr和c.1622G>A;p.Trp541*。
这些新突变可能会影响GALC的结构,进而影响其功能。识别这些突变及其相关表型对于预测预后以及为家庭提供充分的遗传咨询非常重要。