A novel myosin heavy chain gene in human chromosome 19q13.3.

A human myosin heavy chain gene was identified in chromosome 19q13 by computational sequence analysis, RT-PCR and DNA sequencing of the cDNA. The complete cDNA has a length of 6786 bp and comprises 41 exons (40 coding) included in 108 kb of genomic sequence. Alternative splicing variants were also identified. The gene is expressed in a multitude of tissues, but mainly in small intestine, colon and skeletal muscle. The putative protein (228 kDa) carries the common myosin domains and presents high homology with the non-muscle myosin heavy chains (MYH9 and MYH10) as well as the smooth muscle myosin heavy chain MYH11. Nevertheless, phylogenetic analysis indicated that these homologous proteins are more related among themselves than to MYH14, suggesting that possibly this myosin heavy chain should be classified in a new myosin-subfamily.