All Phenotypes Brme1<em1Zhal> MGI Mouse

reproductive system phenotype ( J:291221 )

N	• female fertility and ovary size are similar to controls

azoospermia ( J:291221 )

• no spermatozoa are found in the cauda epididymis

abnormal spermatid morphology ( J:291221 )

• absence of post-meiotic round spermatids and elongated spermatids

abnormal spermatocyte morphology ( J:291221 )

• abnormal nuclei are seen in ~50% of zygotene spermatocytes

abnormal male meiosis ( J:291221 )

• delay or arrest of spermatogenesis at the zygotene/pachytene transition

• defects in synapsis are seen including synapsis partner switch (different regions of one chromosome synapses with more than one partner with at least one partner being a non-homolog) and condensed zygotene (zygotene nuclei with highly condensed chromosomes similar to those seen in pachytene nuclei)

• in pachytene spermatocytes the number of homologous DNA crossovers is reduced with ~25% of autosomes lacking crossover foci

increased male germ cell apoptosis ( J:291221 )

• increase in the number of apoptotic spermatocytes

abnormal seminiferous tubule morphology ( J:291221 )

• tubules contain numerous vacuoles

small testis ( J:291221 )

• much smaller than controls at 8 weeks of age

male infertility ( J:291221 )

abnormal double-strand DNA break repair ( J:291221 )

• presence of foci labeled for the phosphorylated form of the histone variant H2AX indicate the presence of many unrepaired double strand breaks in mid/late pachytene and diplotene spermatocytes