| First Author | West JD | Year | 1993 |
| Journal | Mouse Genome | Volume | 91 |
| Pages | 553 | Mgi Jnum | J:30752 |
| Mgi Id | MGI:78500 | Citation | West JD, et al. (1993) Inheritance of a meiotic abnormality that causes the ovulation of primary oocytes. Mouse Genome 91:553 |
| abstractText | Full text of Mouse Genome contribution: Research News: Inheritance of a Meiotic Abnormality that Causes the Ovulation of Primary Oocytes. Previous studies have demonstrated that the LT/SvKau strain of mice ovulates a high proportion of oocytes as diploid primary oocytes rather than secondary oocytes (e.g. Speirs & Kaufman, Journal of Experimental Zoology 253, 83-87, 1990). These ovulated primary oocytes are arrested at meiotic metaphase I but may be fertilized to produce digynic triploid embryos. In the present study, 40.4% of fertilized eggs from LT/SvKau females were triploid, compared to 1.2% from control C57BL/Ws strain mothers. These two inbred strains were intercrossed to produce eight sets of Fl, F2 and backcross females and the frequency of triploidy was investigated. Segregation of an autosomal, co-dominant gene that has a major influence on the incidence of primary cocyte ovulation is the simplest explanation that fits the results. We suggest that the provisional gene symbol Poo (primary oocyte ovulation) be assigned to this gene, with alleles Pool (the "mutant" allele present in the LT/SvKau strain) and Poob (the normal allele present in C57BL/Ws mice). Poo is incompletely penetrant and has variable expressivity because the proportion of oocytes ovulated as primary oocytes by LT/SvKau mice was variable and, in some cases, nil. In putative Poo1/Poob heterozygotes the frequency of ovulated primary oocytes was increased only marginally (from 1.2% to 6.6%) by the presence of one copy of the Pool allele but this increase was found consistently (in two reciprocal Fl crosses). No evidence was found for tight genetic linkage between Poo and two Mendelian loci (brown on chromosome 4 and glucose phosphate isomerase on chromosome 7), that were segregating in the crosses. The Pool mutant in the LT/SvKau strain of mice provides a valuable resource to study the cell and molecular biology of mammalian oocyte maturation and the control of meiosis. John D. West, Sheila Webb and Matthew H. Kaufman |
