DNA diagnosis of pyruvate dehydrogenase deficiency by PCR-SSCP analysis

1993 Fiscal Year Final Research Report Summary

• Project/Area Number: 04670600
• Research Category: Grant-in-Aid for General Scientific Research (C)
• Allocation Type: Single-year Grants
• Research Field: Pediatrics
• Research Institution: University of Tokushima
• Principal Investigator: KURODA Yasuhiro Univ.of Tokushima Dept.of Pediatr.Professor, 医学部, 教授 (20035471)
• Co-Investigator(Kenkyū-buntansha): ITO Michinori Tokushima Univ.Hosp Dept.of Pediatr.Assistant, 医学部・附属病院, 助手 (40211057)
• Project Period (FY): 1992 – 1993
• Keywords: Lactic acidemia / Pyruvate dehydrogenase / DNA diagnosis / PCR-SSCP

Research Abstract

Defect in pyruvate dehydrogenase(PDH) complex is a major cause of congenital lactic acidemia. Most cases with PDH complex deficiency result from a mutation in the PDH a-subunit (Ela). The gene for Ela is located on the X chromosome. The diagnosis for Ela deficiency is usually estabrished by the measurement of PDH complex activity of the cultured cells. However, the heterozygous female patients with Ela deficiency are misdiagnosed, when the normal X chromosome is predominantly exoressed in the cultured cells. Therefore, for reliable diagnosis of Ela deficiency in female patients, it is essential to define the underlying gene mutation. Then, we used the method of PCR-SSCP and direct sequencing for DNA diagnosis of Ela deficiency. We examined 11 female patients with congenital lactic acidemia, in whom we could not find any defect by the measurement of the enzyme activity of their cultured cells. Three of the 11 female patients had abnormal migration patterns compared with controls. Two of the 3 patients had missense mutations resulting in a changed amino acid residue in the Ela subunit (G89S and G291R). Then, we concluded that PCR-SSCP analysis followed by direct sequencing in female lactic acidemic patients was a useful method for the diagnosis of Ela deficiency.