Increased litter size and super-ovulation rate in congenic C57BL mice carrying a polymorphic fragment of NFR/N origin at theFecq4locus of chromosome 9

Abstract

By analysing N2 mice from a cross between the inbred C57BL strain B10.Q and the NMRI-related NFR/N strain, we recently identified a quantitative trait locus (QTL) influencing litter size. This locus is now denoted Fecq4, and it is present on the murine chromosome 9. In the present paper, we describe how the Fecq4 fragment originating form the NFR/N mouse strain will affect B10.Q mice by means of breeding capacity, super-ovulation rate and embryonic development in vitro. Our results show that both the breeding capacity (number of pups produced/breeding cage during a 5 months period) and the mean litter size are significantly increased in B10.Q.NFR/N-Fecq4 congenic mice. Furthermore. B10.Q.NFR/N-Fecq4 congenic mice (both homozygous and heterozygous) did respond much better to super-ovulation than wild-type mice, resulting in a dramatically increased yield of fertilized 1-cell embryos. In addition, embryos containing the Fecq4 fragment were easy to cultivate in vitro, resulting in a higher yield of embryos reaching the blastocyst stage. We propose that B10.Q.NFR/N-Fecq4 congenic mice may be used to improve breeding or super-ovulation rate in different types of genetically modified mice (on C57BL background) that exhibit severe breeding problems. The Fecq4 fragment has been described in detail, and the possible role of polymorphic candidate genes near the linkage peak (58 Mb) has been discussed. Genes of the cytochrome P450 family (1, 11 and 19), such as Cyp19a1, are assumed to be particularly interesting, since they are known to exhibit female-associated reproductive phenotypes, affecting the ovulation rate, if mutated.

Does Bone Morphogenetic Protein 6 (BMP6) Affect Female Fertility in the Mouse?1

“…Therefore, ovulation and litter size are quantitative processes controlled by a complex interaction among multiple genes. The Bmp6 locus was not identified by the previous QTL linkage analyses as a candidate locus that determines ovulation rate or litter size [69][70][71][72][73]; however, the present study has clearly shown that a deletion in the Bmp6 gene does affect ovulation rate and litter size in mice. Therefore, Bmp6 is probably part of the complex genetic network that determines female fertility.…”

“…Each process is affected by multiple factors, including genetic variability as well as environmental influences. For example, previous studies have identified several quantitative trait loci (QTL) that determine hormone-induced ovulation rate or litter size in mice [69][70][71][72][73]. Therefore, ovulation and litter size are quantitative processes controlled by a complex interaction among multiple genes.…”

Some techniques for sex election in Wistar rats

“…Our results show high newly born number of treatment groups (T1,T2,T3,T4&T5) when compare them with C group, these results are accompanied with (29) who notice that superovulation by hormones treatment lead to increase of newly born number.…”

Genome-wide Association Study Identifies Candidate Genes for Male Fertility Traits in Humans

“…6 Moreover, evidence for genes that also influence normal variation in fertility is provided by quantitative-trait loci (QTL) mapping studies in mice, flies, pigs, and cattle; these studies have identified genetic loci that affect reproductive characteristics in those species. [7][8][9][10][11][12][13][14][15] However, in most QTL mapping studies, the associated regions were too broad to allow for the discovery of specific genes that affect reproductive traits.…”