DMY is a Y-specific DM-domain gene required for male development in the medaka fish.
Although the sex-determining gene Sry has been identified in mammals, no comparable genes have been found in non-mammalian vertebrates. Here, we used recombinant breakpoint analysis to restrict the sex-determining region in medaka fish (Oryzias latipes) to a 530-kilobase (kb) stretch of the Y chromosome. Deletion analysis of the Y chromosome of a congenic XY female further shortened the region to 250 kb. Shotgun sequencing of this region predicted 27 genes. Three of these genes were expressed during sexual differentiation. However, only the DM-related PG17 was Y specific; we thus named it DMY. Two naturally occurring mutations establish DMY's critical role in male development. The first heritable mutant--a single insertion in exon 3 and the subsequent truncation of DMY--resulted in all XY female offspring. Similarly, the second XY mutant female showed reduced DMY expression with a high proportion of XY female offspring. During normal development, DMY is expressed only in somatic cells of XY gonads. These findings strongly suggest that the sex-specific DMY is required for testicular development and is a prime candidate for the medaka sex-determining gene.
Matsuda
Masaru
M
Laboratory of Reproductive Biology, National Institute for Basic Biology, Okazaki 444-8585, Japan.
Nagahama
Yoshitaka
Y
Shinomiya
Ai
A
Sato
Tadashi
T
Matsuda
Chika
C
Kobayashi
Tohru
T
Morrey
Craig E
CE
Shibata
Naoki
N
Asakawa
Shuichi
S
Shimizu
Nobuyoshi
N
Hori
Hiroshi
H
Hamaguchi
Satoshi
S
Sakaizumi
Mitsuru
M
D000595:Amino Acid Sequence; D000818:Animals; D020296:Animals, Congenic; D019457:Chromosome Breakage / Q000235:genetics; D003001:Cloning, Molecular; D003433:Crosses, Genetic; D005260:Female; D029941:Fish Proteins / Q000737:chemistry* / Q000235:genetics*; D018507:Gene Expression Regulation, Developmental; D005838:Genotype; D017403:In Situ Hybridization; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D009990:Oryzias / Q000196:embryology* / Q000235:genetics*; D010641:Phenotype; D020161:Physical Chromosome Mapping; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion / Q000235:genetics; D019849:Sex Determination Processes; D014960:X Chromosome / Q000235:genetics; D014998:Y Chromosome / Q000235:genetics*
D029941:Fish Proteins; D012333:RNA, Messenger