Combined Respiratory Chain Deficiency and <i>UQCC2</i> Mutations in Neonatal Encephalomyopathy: Defective Supercomplex Assembly in Complex III Deficiencies.

ABSTRACT: Vertebrate respiratory chain complex III consists of eleven subunits. Mutations in five subunits either mitochondrial (MT-CYB) or nuclear (CYC1, UQCRC2, UQCRB, and UQCRQ) encoded have been reported. Defects in five further factors for assembly (TTC19, UQCC2, and UQCC3) or iron-sulphur cluster loading (BCS1L and LYRM7) cause complex III deficiency. Here, we report a second patient with UQCC2 deficiency. This girl was born prematurely; pregnancy was complicated by intrauterine growth retardation and oligohydramnios. She presented with respiratory distress syndrome, developed epileptic seizures progressing to status epilepticus, and died at day 33. She had profound lactic acidosis and elevated urinary pyruvate. Exome sequencing revealed two homozygous missense variants in UQCC2, leadin

SUBMITTER: Feichtinger RG 

PROVIDER: S-EPMC5540226 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature