International Mammalian Genome Society

The 15th International Mouse Genome Conference (2001)

Table of Contents * Complex Genetics * Developmental Genetics * Gene Annotation * Gene Discovery * Genome Sequencing * Functional Genomics * Mutagenesis * Presentations * Verne Chapman Memorial Lecture

POSTER 72 - SPERM ANEUPLOIDY IN PL/J MICE: A COMPLEX PHENOTYPE

Prof. Mary Ann Handel
University of Tennessee
Dept. Biochem.and Cellular & Molecular Biology
University of Tennesee
Knoxville, TN 37996-0840
USA

Co-Authors: Pyle, A.
Institutions: Dept. Biochem.and Cellular & Molecular Biology, University of Tennesee, Knoxville, TN 37996-0840

We previously showed that sperm from PL/J males have increased frequencies of both sperm head abnormalities and sperm aneuploidy compared to C57BL/6J sperm.  This trait is complex phenotypically.  During prophase, spermatocytes of PL/J mice exhibit premature chromosome desynapsis.  Abnormalities are more apparent during the first meiotic division, where 34.7% of the PL/J spermatocytes exhibit aberrant spindle morphology (compared to 5.7% for C57BL/6J spermatocytes).  Spindle abnormalities include monopolar spindles, split spindle poles and incomplete spindle formation.  Staining with antibody to pericentrin reveals abnormal numbers of centrosomes in PL/J spermatocytes.  Thus increased frequency of sperm aneuploidy in PL/J males is associated with, and may be caused by, aberrant centrosome and spindle formation.  The traits of sperm aneuploidy and aberrant head morphology are also complex genetically.  F1 progeny of a cross between PL/J and C57BL/6J do not exhibit a higher frequency of either sperm aneuploidy or sperm-head morphology aberrations, as would be expected for a dominant trait.  Among progeny of a backcross of the F1 to PL/J, none of 16 males assessed exhibited elevated frequencies of either sperm aneuploidy or sperm-head morphology abnormalities.  Thus the traits are apparently inherited in a complex manner, with several genes and/or modifiers affecting the generation of sperm aneuploidy and abnormal sperm-head morphology.  (Supported by NIH HD33816 to MAH)