Moseilhy Ahmed, Hassan Magdy M, El Abd Heba S A, Mohammad Shaimaa A, El Bekay Rajaa, Abdel-Motal Ussama M, Ouhtit Allal, Zaki Osama K, Zayed Hatem
Medical Genetics Unit, Pediatric Department, Faculty of Medicine, Ain Shams University Hospital, Cairo, 11665, Egypt.
Department of Biochemistry, Faculty of Science, Ain Shams University, Cairo, Egypt.
Metab Brain Dis. 2017 Feb;32(1):35-40. doi: 10.1007/s11011-016-9879-x. Epub 2016 Aug 1.
To characterize an Egyptian patient with glutaric acidemia type I (GA I) and to identify the causative mutation(s) that may be responsible for the disease phenotype. MRI was performed on the patient using the 1.5 T magnet, biochemical analysis was carried out using gas chromatography/mass spectrometry on the patient's dried blood spot, and the patient's organic acids were measured in dried blood and a urine sample using MS/MS and GC/MS, respectively. Total RNA was isolated from the patient's peripheral blood, and the synthesized cDNA was bi-directionally sequenced. The patient exhibited clinical features and MRI findings compatible with a diagnosis of GA I. The abnormal elevation of organic acids in the urine supported the presence of glutaryl-CoA dehydrogenase deficiency. Gene sequencing revealed a novel homozygous frameshift mutation, c.644_645insCTCG; p.(Pro217Leufs*14), in exon 8 of the GCDH gene. The present study revealed a novel frameshift mutation responsible for a severe GA I phenotype in an Egyptian patient. This novel mutation will ultimately contribute to a better understanding of the molecular pathology of the disease and shed light on the intricacies of the genotype-phenotype correlation of GA I disease.
为了对一名患有I型戊二酸血症(GA I)的埃及患者进行特征描述,并确定可能导致该疾病表型的致病突变。使用1.5 T磁体对患者进行了MRI检查,使用气相色谱/质谱法对患者的干血斑进行了生化分析,分别使用串联质谱法(MS/MS)和气相色谱/质谱法(GC/MS)对患者干血和尿液样本中的有机酸进行了测量。从患者外周血中分离出总RNA,并对合成的cDNA进行双向测序。该患者表现出与GA I诊断相符的临床特征和MRI结果。尿液中有机酸的异常升高支持戊二酰辅酶A脱氢酶缺乏的存在。基因测序揭示了GCDH基因第8外显子中的一个新的纯合移码突变,c.644_645insCTCG;p.(Pro217Leufs*14)。本研究揭示了一个导致埃及患者严重GA I表型的新的移码突变。这一新突变最终将有助于更好地理解该疾病的分子病理学,并阐明GA I疾病基因型-表型相关性的复杂性。