Insight into the Possible Formation Mechanism of the Intersex Phenotype of Lanzhou Fat-Tailed Sheep Using Whole-Genome Resequencing

Abstract

Intersex, also known as hermaphroditism, is a serious hazard to animal husbandry and production. The mechanism of ovine intersex formation is not clear. Therefore, genome-wide resequencing on the only two intersex and two normal Lanzhou fat-tailed (LFT) sheep, an excellent but endangered Chinese indigenous sheep breed, was performed. Herein, the deletion of homologous sequences of the goat polled intersex syndrome (PIS) region (8787 bp, 247747059–247755846) on chromosome 1 of the LFT sheep was not the cause of the ovine intersex trait. By detecting the selective sweep regions, we found that the genes related to androgen biosynthesis and follicle stimulating hormone response items, such as steroid 5 alpha-reductase 2 (SRD5A2), steroid 5 alpha-reductase 3 (SRD5A3), and pro-apoptotic WT1 regulator (PAWR), may be involved in the formation of intersex traits. Furthermore, the copy number variations of the four regions, chr9: 71660801–71662800, chr1: 50776001–50778000, chr4: 58119201–58121600, and chr16: 778801–780800, may affect the expression of the zinc finger protein, FOG family member 2 (ZFPM2), LIM homeobox 8 (LHX8), inner mitochondrial membrane peptidase subunit 2 (IMMP2L) and slit guidance ligand 3 (SLIT3) genes, respectively, which contribute to the appearance of intersex traits. These results may supply a theoretical basis for the timely detection and elimination of intersex individuals in sheep, which could accelerate the healthy development of animal husbandry.

Whole genome re-sequencing reveals artificial and natural selection for milk traits in East Friesian sheep

“…The candidate genes B4GALNT4 ( 33 ) involved in lactose synthesis, RCOR1 ( 34 ) related to milk yield and SH3D19 related to lactation process in sheep were also identified ( 35 ). In addition, our results contain a large number of candidate genes related to production traits, such as reproductive trait candidates: FSIP2 ( 17 ), CD226 ( 36 ), SLC44A5 ( 37 ), GPR83 ( 38 ), SUN5 ( 39 ), GPR173 ( 40 ), LHX8 ( 41 ), SIRT3 ( 42 ), FGF16 ( 43 ), POU3F4 ( 44 ), these genes affect reproductive traits by influencing days of estrus, luteal gland, participating in reproductive regulation, and hypothalamic-pituitary-gonadal axis regulation. For example, the candidate genes for wool traits: RALY ( 45 ), GLI2 ( 46 ), TXNRD3 ( 47 ), EIF2S2 ( 45 ), IRF2BP2 ( 48 ), etc.…”

The Complex and Diverse Genetic Architecture of the Absence of Horns (Polledness) in Domestic Ruminants, including Goats and Sheep

“…Please note that a list of sheep breeds belonging to different horn status groups can be found in Table 2. The localization of the homologous sequences of the caprine PIS region ruled out the possibility that intersexuality in sheep has the same or similar underlying genetic causes as in goats [74]. However, there is also no evidence of a comparable relationship between polledness and intersexuality in sheep.…”

Combining Transcriptome and Whole Genome Re-Sequencing to Screen Disease Resistance Genes for Wheat Dwarf Bunt

“…The individual genome could be detected using WGRS technology and screened for candidate disease resistance genes based on the known reference genome sequence [25]. Meanwhile, a large number of SNPs and Indels could be obtained using WGRS [26]. Additionally, these mutants are closely related to an individual's biological traits and are extremely important in a study screening for candidate disease resistance genes.…”