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Published on: August 15, 2019
Genetic analysis of the rat hypodactylous mutation
D Krenová1, Z Jirsová, D Housa
1Institute of Biology and Medical Genetics, 1st Medical Faculty, Charles University, Prague, Czech Republic.
Abstract:
Autosomal recessive rat hypodactylous mutation Hd leads in homozygous condition to reductive changes of the digital arch of all feet. There is a variable preaxial reduction of the number of fingers in both sexes. Moreover, homozygous males are sterile. Testes of homozygous Hd/Hd and +/Hd adult rats were examined in the light and electron microscopes. Spatial organization of stages of the spermatogenetic cycle was not confirmed in Hd/Hd testes comparing with +/Hd males. Significant decrease in the number of germ cells in seminiferous tubules of Hd/Hd testes was accompanied with loosening and vacuolization of the seminiferous epithelium. The assignment of the Hd locus to RNO10 excluded the suspected homology between rat and mouse Hd mutations. More precise mapping using microsatellite markers revealed close linkage of the Hd locus with the D1OMit8 marker defining Syb2 gene coding for synaptobrevin 2. A chromosomal segment of RNO10 carrying Hd and Syb genes is being incrossed onto BN and SHR inbred strains in order to examine the modifying influences of different genetic backgrounds.
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