Sequencing analysis of the mitochondrial DNA encoded ND genes , the nuclear DNA encoded NDUFV 1 , NDUFS 1 , NDUFS 2 , NDUFS 4 , NDUFS 6 , NDUFS 7 , NDUFS 8 , and NDUFAB 1 genes , and the complex 1 assembly factor CIA 30 gene revealed a novel homozygous L231V mutation ( c . 691C > G ) in the NDUFS 1 gene . ^^^