Identification of a possible control element, Mt5, in the major noncoding region of mitochondrial DNA by intraspecific nucleotide conservation.

Nucleotide sequences throughout the whole major noncoding region of mitochondrial DNA of 18 subjects were determined. Previously identified control elements were classified into three groups according to the degree of intraspecific nucleotide conservations: strictly conserved elements (LSP, HSP, Mt3, Mt3 on H-strand, mtTF1-element for HSP), relatively conserved elements (CSB-III, Mt4 on H-strand, and mtTF1-element for LSP), and variable elements (TAS, CSB-I, CSB-II). Moreover, alignment of nucleotide conservations disclosed a stretch of conserved sequence (5'-ATGCTTACAAGCAAG-3', nucleotide number 16, 194-16,208, designated as Mt5 element) in the middle of the hypervariable segment. Nucleotide conservation of this element was not only intraspecific but also interspecific.