DNA sequence analysis of overlapping shotgun and restriction fragments have revealed the entire sequence of the human lens fiber cell intrinsic membrane protein MP19 gene (also termed MP17, MP18, and MP20). The 8,056 bp MP19 gene contains 5 exons encoding a mature protein of 173 amino acids, which displayed a very high degree of identity (91%) with that of bovine MP19, deduced from a bovine cDNA sequence. The exons range in size from 52 bases (exon 1) to about 340 bases (exon 5). The introns consist of two large segments (introns B and C) of about 4,700 bases and 1,800 bases, respectively, and two small segments (intron A and D) of about 450 and 250 bases each. SevenAlufamily DNA repeats are found within the human MP19 gene. The sequenced gene includes 100 bases of 5′flanking sequence.