[1]
Magdy Mohamed Mahmoud Hassan, Department of Biochemistry, Faculty of Science, Ain Shams University, Cairo, Egypt.
[2]
Nahla Samir Hassan, Department of Biochemistry, Faculty of Science, Ain Shams University, Cairo, Egypt.
[3]
Ehab Abd Elsalam Mahmoud, Al Rahma Labs, Cairo, Egypt.
[4]
Ahmed Mohamed Moseilhy, Medical Genetics Unit, Pediatric Department, Faculty of Medicine, Ain Shams University Hospital, Cairo, Egypt.
[5]
Dina Mohamed Seoudi, Department of Biochemistry, Faculty of Science, Ain Shams University, Cairo, Egypt.
[6]
Osama Kamal Zaki, Medical Genetics Unit, Pediatric Department, Faculty of Medicine, Ain Shams University Hospital, Cairo, Egypt.
Maple syrup urine disease (MSUD) is a rare, autosomal recessive disorder of branched chain amino acid (BCAA) metabolism caused by dysfunction of the multienzyme branched-chain alpha-keto acid dehydrogenase (BCKDH) complex. The disorder can be caused by mutations within any of the BCKDHA, BCKDHB, DBT and DLD genes encoding the branched-chain alpha-keto acid dehydrogenase complex. The aim of the study was to identify the molecular genetic cause of classic MSUD in an Egyptian female neonate reported by newborn screening program. The genetic analyses involved polymerase chain reaction (PCR) and sequencing of the BCKDHA gene (E1 ά). Sequencing of the amplified cDNA disclosed at codon 438 of the mature El ά polypeptide a base substitution changing a tyrosine to an asparagine residue (Y438N). This mutation strongly suggests that the BCKDHA substitution is pathogenic and is the cause of classic MSUD in this patient.
Maple Syrup Urine Disease, Msud Bckdha, GC/MS, LC/MS-MS
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