International Mammalian Genome Society


The 13th International Mouse Genome Conference
October 31-November 3, 1999

Table of Contents * Structure * Bioinformatics * Sequence * Mapping * New Tools * Gene Discovery * Developmental * Mutagenesis * Functional Genomics

D9 Physical and Transcriptional Mapping of the Juvenile Spermatogonial Depletion (jsd) Critical Interval

Holly Boettger-Tong1, Nicholas Levy1,3, Alexander Agulnik1, M. Teresa Ty1, Yoshitake Nishimune4 and Colin Bishop1,2. 1Department of Obstetrics and Gynecology; 2Department of Molecular and Human Genetics, Baylor College of Medicine, Houston TX; 3Inserm U491 "Génétique Médicale et développement" Faculté de Médecine de la Timone 13385 Marseille, France; 4Research Institute for Microbial Diseases, Osaka UniversityYamada-oka, Suita City, Osaka Japan

Spermatogenesis provides the haploid vehicle through which paternal genetic information may be represented in the offspring. The production of mature spermatozoa is a highly complex sequence of coordinated mitotic, meiotic and differentiative events; perturbation at key stages in this process results in sterility. In mice, the juvenile spermatogonial depletion (jsd) mutation results in a single wave of spermatogenesis, followed by failure of type A spermatogonial stem cells to proliferate, rendering male animals sterile. No other abnormalities are apparent in jsd males, and female fertility is unaffected by this mutation. Identification of the defect responsible for this phenotype would provide considerable insight into the regulation of spermatogonial stem cell renewal and may provide for the design of novel therapies to restore fertility.

Previous reports had linked the jsd mutation to Chromosome 1, approximately 5cM from Idh-1. We have refined this map position, using backcross offspring produced by mating (C57BL/6 X C3H/HeJ)F1 jsd/+ males to B6 jsd/jsd females. A number of chromosome 1 markers were used to genotype 800 male progeny; the phenotype of these animals was determined at 8-10 weeks of age. This analysis resulted in a refinement of the jsd critical interval to approximately 1cM between markers 24IVB9 and D1Mit334, with 100% linkage of the jsd phenotype to marker 24IVB9. To generate a physical map of this region, probes from the critical interval were hybridized to high density mouse BAC library filters (BAC PAC Resources, Roswell Park). BACs were assembled into contigs by PCR with both known markers and with STSs generated from BAC ends. Contigs were extended by walking out from unique BAC ends. BACs were subcloned into exon trapping vectors, and the resultant products sequenced. Database searches of products with an open reading frame were used to identify repeat elements or previously identified genes or expressed sequence tags (ESTs). RT-PCR reactions using primers designed from one such candidate has identified a novel gene which is expressed in a number of tissues, including testis. Further analysis of this and other products will provide a transcriptional map of this region, and will provide candidate genes for the jsd mutation.

 


Abstracts * Officers * Bylaws * Application Form * Meeting Calendar * Contact Information * Home * Resources * News and Views * Membership

Base url http://imgs.org
Last modified: Saturday, November 3, 2012