The object of the present invention is to provide a fundamental therapy to mitochondrial genetic diseases caused by mutation of the mitochondrial (mt)DNA, and a pharmaceutical composition used for the same.The object can be solved by a polyamide compound binding to a target double-stranded mtDNA comprising A/T pair consisting of first A of the following sense-stranded DNA and the corresponding T, A/T pair consisting of 8th A of the following sense-stranded DNA and the corresponding T, G/C pair consisting of 9th G of the following sense-stranded DNA and the corresponding C, G/C pair consisting of 14th G of the following sense-stranded DNA and the corresponding C, T/A pair consisting of 15th T of the following sense-stranded DNA and the corresponding A, or the like, in the double-stranded DNA consisting of the sense-stranded DNA having base sequence of 5′-ATGGCAGAGCCCGGTAATCGCATAA-3′ (SEQ ID NO: 1) and the antisense-stranded DNA having base sequence of 5′-TTATGCGATTACCGGGCTCTGCCAT-3′ (SEQ ID NO: 2).
