It is indicated that PTH is extremely conserved among
higher vertebrates. Comparison of the whole nucleotide
sequences and 115-amino-acid sequences (prepro–PTH)
of the PTH gene of human and 12 species of nonhuman
primates also showed a very high homology, especially
between humans and chimpanzees (P. troglodytes and P.
paniscus), where 100% homology of amino acid sequences
was observed. This result supports a closer relationship
between humans and chimpanzees than between
humans and the other great apes (Zimonjic et al.,
1997; Chen and Li, 2001