Mutations in cytochrome B gene effects female reproduction of Ghungroo pig

Role of mucin 2 gene for growth in Anas platyrhynchos: a novel report

Introduction

The mucin gene is expressed in the mucous membrane of the inner layer of the internal organs. Intestinalmucin 2 (MUC2), amajor gel-formingmucin, represents a primary barrier component of mucus layers.

Materials and methods

This is the first report on the role of mucin genes in growth traits in animals. In this study, we randomly studied Bengal ducks (Anas platyrhynchos) reared from day old to 10 weeks of age under an organized farm and studied the growth parameters as well as body weight and average daily body weight gain.

Result and discussion

We characterized the mucin gene for Bengal ducks and observed glycosylation and EGF1 (EGF-like domain signature) as important domains for growth traits in ducks. We observed a better expression profile for the mucin gene in high-growing ducks in comparison to that of low-growing ducks with real-time PCR. Hence, the mucin gene may be employed as a marker for growth traits.

The ND1 and CYTB genes polymorphisms associated with in vitro early embryo development of Sanjabi sheep

This study aimed to investigate the association between polymorphisms of ND1 and CYTB genes and in vitro early embryo development of Sanjabi sheep. Blood and ovarian samples were collected from a local slaughterhouse. The cumulus-oocyte complexes with a diameter greater than 3 mm were aspirated from follicles, and in vitro maturation (IVM) and in vitro culture (IVC) rates of them were recorded. A respective 1200 bp and 980 bp fragments of ND1 and CYTB genes were genotyped using a modified single strand conformation polymorphism (SSCP) method. The results of this study revealed that four different patterns, named as A, B, C, and D were observed for both ND1 and CYTB genes. The ND1 gene polymorphisms had significant effects on the IVM and IVC rate (p < 0.05). The pattern C of the ND1 gene significantly increased the IVM rate compared to the patterns A, B and D. For the IVC, the highest and lowest means were related to the C and B patterns, respectively. The CYTB gene polymorphisms also had significant effects on IVC (p < 0.01), but the IVM did not affected (p = 0.07). Here, the pattern D had the highest and the pattern C had the lowest means for both IVM and IVC rates.

The relationship between mitochondrial ND5 gene polymorphisms and in vitro embryo production in Sanjabi sheep

The aim of this study was to investigate mitochondrial ND5 gene polymorphisms and their relationship with in vitro maturation (IVM) and in vitro culture (IVC) of Sanjabi sheep. Blood and ovarian samples of adult ewes were obtained from a local slaughterhouse. For each ovarian sample, cumulus-oocyte complexes larger than 3 mm in diameter were aspirated from follicles, and their IVM and IVC rates were recorded. A 666-bp fragment of the ND5 gene was amplified using the polymerase chain reaction. The samples were genotyped using a modified single-stranded conformation polymorphism (SSCP) method, and an association study was conducted with IVM and IVC rates. Six different SSCP patterns, designated A, B, C, D, E and F with respective frequencies of 8, 47, 4, 4, 32 and 5%, respectively, were observed. According to the results of association analysis, there was no significant association between the ND1 gene polymorphisms and the IVM and IVC rates (P > 0.05).

A novel (ATC)n microsatellite locus is associated with litter size in an indigenous Chinese pig

Simple sequence repeats (SSRs) are an important part of the genome and have become powerful auxiliary DNA markers in animal breeding using marker-assisted selection (MAS). Based on previous sequencing data of Qinghai Bamei pigs, a total of three novel candidate SSR loci were analysed in this study. Time-of-flight mass spectrometry (TOF-MS) was used for SSR genotyping, and association analyses between SSRs and the litter size of Qinghai Bamei sows was also performed. The results of genotyping showed that the (ATC)_n -P1, (AC)_n -P2 and (AC)_n -P3 loci had 2, 3 and 18 genotypes, respectively; 2, 3 and 8 alleles were also identified at these loci. Except for the (AC)_n -P2 locus, the polymorphism information content (PIC) values of other loci were greater than 0.25. Association analyses indicated that only the (ATC)_n -P1 locus was significantly associated with the litter size of Qinghai Bamei sows (p = .047). Compared to 189-/189- genotype, individuals with the 189-/195- genotype had the senior litter size, which was 9.04 ± 0.21. Our results enrich the data on SSRs in Qinghai Bamei pigs and indicate that (ATC)_n -P1 is a candidate locus for MAS in the pig industry.

Mutation in Cytochrome B gene causes debility and adverse effects on health of sheep

Cytochrome B is the mitochondrial protein, which functions as part of the electron transport chain and is the main subunit of transmembrane cytochrome bc1 and b6f complexes affecting energy metabolism through oxidative phosphorylation. The present study was conducted to study the effect of mutation of Cytochrome B gene on the health condition of sheep, which the first report of association of mitochondrial gene with disease traits in livestock species. Non-synonymous substitutions (F33 L and D171N) and Indel mutations were observed for Cytochrome B gene, leading to a truncated protein, where anemia, malfunctioning of most of the vital organs as liver, kidney and mineral status was observed and debility with exercise intolerance and cardiomyopathy in extreme cases were depicted. These findings were confirmed by bioinformatics analysis, haematological and biochemical data analysis, and other phenotypical physiological data pertaining to different vital organs. The molecular mechanism of cytochrome B mutation was that the mutant variant interferes with the site of heme binding (iron containing) domain and calcium binding essential for electron transport chain. Mutation at amino acid site 33 is located within transmembrane helix A, a hydrophobic environment at the Qi site and close to heme binding domain, and mutation effects these domain and diseases occur. Thermodynamic stability was also observed to decrease in mutant variant. Sheep Cytochrome B being genetically more similar to the human, it may be used as a model for studying human diseases related to cytochrome B defects. Future prospect of the study includes the therapeutic application of recombinant protein, gene therapy and marker-assisted selection of disease-resistant livestock.

Mitochondrial replacement therapy - a new remedy for defects in reproduction

Mitochondria is an important subcellular organelle with the prime function being energy metabolism and supply of energy to the body cells for carrying out the vital functions. Energy is the primary requisite for the reproductive organs of both male and female for carrying out the normal functions. In the present article, we have described how mutation in mitochondrial DNA lead to defects in male and female reproduction. Mitochondria is an integral part of the mid-piece of sperm and also has role in other parts of male reproductive system. Similarly, mitochondrial DNA has role in female reproductive system including ovulation, zygote activation, fertilization, oocyte maturation and embryo development. Mitochondrial defect are collectively named as "mystondria" (mysterious diseases of mitochondria) and may be corrected through mitochondrial replacement therapy, popularly known as three parent baby concept, since there are no other scope for cure or treatment. Two approaches for mitochondrial replacement therapy are pronuclear transfer and spindle transfer. The first three parent baby was developed in April 2016 through mitochondrial replacement therapy. The present review is aimed at functional relevance of three-parent baby concept in animal reproduction.