scholarly journals Genetic Diversity and Population Structure for Resistance and Susceptibility to Mastitis in Braunvieh Cattle

2021 ◽  
Vol 8 (12) ◽  
pp. 329
Author(s):  
Mitzilin Zuleica Trujano-Chavez ◽  
Reyna Sánchez-Ramos ◽  
Paulino Pérez-Rodríguez ◽  
Agustín Ruíz-Flores

Mastitis is a disease that causes significant economic losses, since resistance to mastitis is a difficult trait to be improved due to its multifactorial occurrence. Therefore, our objective was to characterize a Mexican Braunvieh cattle population for genetic resistance and susceptibility to mastitis. We used 66 SNP markers for 45 candidate genes in 150 animals. The average heterozygosity was 0.445 ± 0.076, a value higher than those reported for some European breeds. The inbreeding coefficient was slightly negative for resistance to subclinical (−0.058 ± 0.055) and clinical (−0.034 ± 0.076) mastitis, possibly due to low selection for the immunological candidate genes that influence these traits. The genotypic profiles for the candidate loci per K-means group were obtained, as well as the group distribution through the graphics of the principal component analysis. The genotypic profiles showed high genetic diversity among groups. Resistance to clinical mastitis had the lowest presence of the heterozygous genotypes. Although the percentage of highly inbred animals (>50%) is up to 13.3%, there are highly heterozygous groups in terms of the studied traits, a favorable indicator of the presence of genetic diversity. The results of this study constitute evidence of the genetic potential of the Mexican Braunvieh population to improve mastitis-related traits.

Genes ◽  
2019 ◽  
Vol 10 (9) ◽  
pp. 676 ◽  
Author(s):  
Farahani ◽  
Maleki ◽  
Mehrabi ◽  
Kanouni ◽  
Scheben ◽  
...  

Characterization of genetic diversity, population structure, and linkage disequilibrium is a prerequisite for proper management of breeding programs and conservation of genetic resources. In this study, 186 chickpea genotypes, including advanced “Kabuli” breeding lines and Iranian landrace “Desi” chickpea genotypes, were genotyped using DArTseq-Based single nucleotide polymorphism (SNP) markers. Out of 3339 SNPs, 1152 markers with known chromosomal position were selected for genome diversity analysis. The number of mapped SNP markers varied from 52 (LG8) to 378 (LG4), with an average of 144 SNPs per linkage group. The chromosome size that was covered by SNPs varied from 16,236.36 kbp (LG8) to 67,923.99 kbp (LG5), while LG4 showed a higher number of SNPs, with an average of 6.56 SNPs per Mbp. Polymorphism information content (PIC) value of SNP markers ranged from 0.05 to 0.50, with an average of 0.32, while the markers on LG4, LG6, and LG8 showed higher mean PIC value than average. Unweighted neighbor joining cluster analysis and Bayesian-based model population structure grouped chickpea genotypes into four distinct clusters. Principal component analysis (PCoA) and discriminant analysis of principal component (DAPC) results were consistent with that of the cluster and population structure analysis. Linkage disequilibrium (LD) was extensive and LD decay in chickpea germplasm was relatively low. A few markers showed r2 ≥ 0.8, while 2961 pairs of markers showed complete LD (r2 = 1), and a huge LD block was observed on LG4. High genetic diversity and low kinship value between pairs of genotypes suggest the presence of a high genetic diversity among the studied chickpea genotypes. This study also demonstrates the efficiency of DArTseq-based SNP genotyping for large-scale genome analysis in chickpea. The genotypic markers provided in this study are useful for various association mapping studies when combined with phenotypic data of different traits, such as seed yield, abiotic, and biotic stresses, and therefore can be efficiently used in breeding programs to improve chickpea.


Author(s):  
Somayeh Farahani ◽  
Mojdeh Maleki ◽  
Rahim Mehrabi ◽  
Homayoun Kanouni ◽  
Reza Talebi

Characterization of genetic diversity, population structure and linkage disequilibrium is prerequisite for proper management of breeding programs and conservation of genetic resources. In this study, 186 chickpea genotypes including advanced “Kabuli” breeding lines and Iranian landrace “Desi” chickpea genotypes were genotyped using DArTseq-Based SNP markers. Out of 3339 SNPs, 1152 markers with known chromosomal position were selected for genome diversity analysis. The number of mapped SNP markers varied from 52 (LG8) to 378 (LG4), with an average of 144 SNPs per linkage group. The chromosome size that covered by SNPs varied from 16236.36 kbp (LG8) to 67923.99 kbp (LG5), while LG4 showed higher number of SNPs, with an average of 6.56 SNPs per Mbp. Polymorphism information content (PIC) value of SNP markers ranged from 0.05 to 0.50, with an average of 0.32, while the markers on LG4, LG6 and LG8 showed higher mean PIC value than average. Un-weighted Neighbor Joining cluster analysis and Bayesian-based model population structure grouped chickpea genotypes into four distinct clusters. Principal component analysis (PCoA) and Discriminant Analysis of Principal Component (DAPC) results were consistent with that of the cluster and population structure analysis. Linkage disequilibrium (LD) was extensive and LD decay in chickpea germplasm was relatively low. A few markers showed r2≥0.8, while 2961 pairs of markers showed complete LD (r2=1) and a huge LD block was observed on LG4. High genetic diversity and low kinship value between pairs of genotypes suggesting the presence of a high genetic diversity among studied chickpea genotypes. This study also demonstrated the efficiency of DArTseq-based SNP genotyping for large scale genome analysis in chickpea. The genotypic markers provided in this study are useful for various association mapping studies when combined with phenotypic data of different traits such as seed yield, abiotic and biotic stresses and therefore can be efficiently used in breeding programs to improve chickpea.


2021 ◽  
Author(s):  
Zeliang Zhang ◽  
Junduo Wang ◽  
Zhaolong Gong ◽  
Yajun Liang ◽  
Xiantao Ai ◽  
...  

Genetic diversity, kinship and population genetic structure analyses of Gossypium hirsutum germplasm can provide a better understanding of the origin and evolution of G. hirsutum biodiversity. In this study, 1313331 SNP molecular markers were used to construct a phylogenetic tree of each sample using MEGAX, to perform population structure analysis by ADMIXTURE software and principal component analysis (PCA) by EIGENSOFT software, and to estimate relatedness using SPAGeDi. ADMIXTURE software divided the experimental cotton population into 16 subgroups, and the Gossypium hirsutum samples could be roughly clustered according to source place, but there were some overlapping characteristics among samples. The experimental cotton population was divided into six groups according to source to calculate the genetic diversity index (H), and the obtained value (0.306) was close to that for germplasm collected by others in China. Cluster 4 had a relatively high genetic diversity level (0.390). The degrees of genetic differentiation within the experimental cotton population groups were low (the population differentiation indexes ranged from 0.02368 to 0.10664). The genetic distance among cotton accessions varied from 0.000332651 to 0.562664014, with an average of 0.25240429. The results of this study may provide a basis for mining elite alleles and using them for subsequent association analysis.


Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 366
Author(s):  
Riccardo Moretti ◽  
Dominga Soglia ◽  
Stefania Chessa ◽  
Stefano Sartore ◽  
Raffaella Finocchiaro ◽  
...  

Mastitis is an infectious disease affecting the mammary gland, leading to inflammatory reactions and to heavy economic losses due to milk production decrease. One possible way to tackle the antimicrobial resistance issue stemming from antimicrobial therapy is to select animals with a genetic resistance to this disease. Therefore, aim of this study was to analyze the genetic variability of the SNPs found in candidate genes related to mastitis resistance in Holstein Friesian bulls. Target regions were amplified, sequenced by Next-Generation Sequencing technology on the Illumina® MiSeq, and then analyzed to find correlation with mastitis related phenotypes in 95 Italian Holstein bulls chosen with the aid of a selective genotyping approach. On a total of 557 detected mutations, 61 showed different genotype distribution in the tails of the deregressed EBVs for SCS and 15 were identified as significantly associated with the phenotype using two different approaches. The significant SNPs were identified in intergenic or intronic regions of six genes, known to be key components in the immune system (namely CXCR1, DCK, NOD2, MBL2, MBL1 and M-SAA3.2). These SNPs could be considered as candidates for a future genetic selection for mastitis resistance, although further studies are required to assess their presence in other dairy cattle breeds and their possible negative correlation with other traits.


Plants ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1190 ◽  
Author(s):  
Eunju Seo ◽  
Kipoong Kim ◽  
Tae-Hwan Jun ◽  
Jinsil Choi ◽  
Seong-Hoon Kim ◽  
...  

Cowpea is one of the most essential legume crops providing inexpensive dietary protein and nutrients. The aim of this study was to understand the genetic diversity and population structure of global and Korean cowpea germplasms. A total of 384 cowpea accessions from 21 countries were genotyped with the Cowpea iSelect Consortium Array containing 51,128 single-nucleotide polymorphisms (SNPs). After SNP filtering, a genetic diversity study was carried out using 35,116 SNPs within 376 cowpea accessions, including 229 Korean accessions. Based on structure and principal component analysis, a total of 376 global accessions were divided into four major populations. Accessions in group 1 were from Asia and Europe, those in groups 2 and 4 were from Korea, and those in group 3 were from West Africa. In addition, 229 Korean accessions were divided into three major populations (Q1, Jeonra province; Q2, Gangwon province; Q3, a mixture of provinces). Additionally, the neighbor-joining tree indicated similar results. Further genetic diversity analysis within the global and Korean population groups indicated low heterozygosity, a low polymorphism information content, and a high inbreeding coefficient in the Korean cowpea accessions. The population structure analysis will provide useful knowledge to support the genetic potential of the cowpea breeding program, especially in Korea.


Caryologia ◽  
2021 ◽  
Vol 74 (2) ◽  
pp. 149-161
Author(s):  
Jing Ma ◽  
Wenyan Fan ◽  
Shujun Jiang ◽  
Xiling Yang ◽  
Wenshuai Li ◽  
...  

Genetic diversity studies are essential to understand the conservation and management of plant resources in any environment. The genus Consolida (DC.) Gray (Ranuculaceae) belongs to tribe Delphinieae. It comprises approximately 52 species, including the members of the genus Aconitella Spach. No detailed Random Amplified Polymorphic DNA (RAPD) studies were conducted to study Consolida genetic diversity. Therefore, we collected and analyzed 19 species from 12 provinces of regions. Overall, one hundred and twenty-seven plant specimens were collected. We showed significant differences in quantitative morphological characters in plant species. Unweighted pair group method with arithmetic mean and principal component analysis (PCA) divided Consolida species into two groups. All primers produced polymorphic amplicons though the extent of polymorphism varied with each primer. The primer OPA-06 was found to be most powerful and efficient as it generated a total of 24 bands of which 24 were polymorphic. The Mantel test showed correlation (r = 0.34, p=0.0002) between genetic and geographical distances. We reported high genetic diversity, which clearly shows the Consolida species can adapt to changing environments since high genetic diversity is linked to species adaptability. Present results highlighted the utility of RAPD markers and morphometry methods to investigate genetic diversity in Consolida species. Our aims were 1) to assess genetic diversity among Consolida species 2) is there a correlation between species genetic and geographical distance? 3) Genetic structure of populations and taxa.


2021 ◽  
Author(s):  
Tanzeem Fatima ◽  
Ashutosh Srivastava ◽  
Vageeshbabu S Hanur ◽  
M. Srinivasa Rao

Sandalwood (Santalum album L.) is highly valued aromatic tropical tree. It is known for its high quality heartwood and oil. In this study 39 genic and genomic SSR markers were used to analyze the genetic diversity and population structure of 177 S. album accessions from 14 populations of three states in India. High genetic diversity was observed in terms of number of alleles 127 expected heterozygosity (He) ranged from 0.63-0.87 and the average PIC was 0.85. The selected population had relatively high genetic diversity with Shannons information index (I) >1.0. 0.02 mean coefficient of genetic differentiation (FST) and 10.55 gene flow were observed. AMOVA revealed that 92% of the variation observed within individuals. Based on cluster and Structure result individuals were not clustered as per their geographical origin. Furthermore the clusters were clearly distinguished by principal component analysis analysis and the result revealed that PC1 reflected the moderate contribution in genetic variation (6%) followed by PC2 (5.5%). From this study, high genetic diversity and genetic differentiation was found in S. album populations. The genetic diversity information of S. album populations can be used for selection of superior genotypes and germplasm conservation to promote the tree improvement of S. album populations.


2019 ◽  
Vol 75 (05) ◽  
pp. 6254-2019
Author(s):  
ANNA ORŁOWSKA ◽  
MARCIN SMRECZAK ◽  
JERZY ROLA

Bluetongue (BT) is a vector-borne viral disease effecting ruminants caused by bluetongue virus (BTV), transmitted mainly by bites from midges of the genus Culicoides. Since the end of 20th century, BTV is endemic in several European countries and the disease is caused mainly by BTV-8 and BTV-4 infections. Bluetongue virus is characterized by high genetic diversity. To date, over 29 BTV serotypes have been documented, including recently discovered atypical serotypes BTV (25–27). The disease has a high economic impact as it causes economic losses due to animal mortality, reduced productivity and restrictions on the movement of animals. Several reports and numerous observations indicate the contribution of animal movements to the spread of BTV infections. Thus, bluetongue surveillance that includes testing of sentinel animals as well as virological testing of animals susceptible to BTV infection imported from restricted zones due to the presence of BTV is a key factor in maintaining a BT-free status


2021 ◽  
Author(s):  
Hui Jiang ◽  
Gen Pan ◽  
Touming Liu ◽  
Li Chang ◽  
Siqi Huang ◽  
...  

Abstract Flax is an important oil and fibre crop grown in Northern Europe, Canada, India, and China. The development of molecular markers has accelerated the process of flax molecular breeding and has improved yield and quality. Presently, simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers in the whole genome have been developed for flax. However, the development of flax insertion/deletion (InDel) markers has not been reported. A total of 17,110 InDel markers were identified by comparing whole-genome re-sequencing data of two accessions (87-3 and 84-3) with the flax reference genome. The length of InDels ranged from 1–277 bp, with 1–15 bp accounting for the highest rate (95.55%). The most common InDels were in the form of single nucleotide (8840), dinucleotide (3700), and trinucleotide (1349), and chromosome 2 (1505) showed the highest number of InDels among flax chromosomes, while chromosome 10 (913) presented with the lowest number. From 17,110 InDel markers, 90 primers that were evenly distributed in the flax genome were selected. Thirty-two pairs of polymorphic primers were detected in two flax accessions, and the polymorphism rate was 40.70%. Furthermore, genetic diversity analysis, population structure and principal component analyse (PCA) divided 69 flax accessions into two categories, namely oilseed flax and fibre flax using 32 pairs of polymorphic primers. Additionally, correlation analysis showed that InDel-26 and InDel-81 were associated with oil content traits, and two candidate genes (lus10031535 and lus10025284) tightly linked to InDel-26 or InDel-81, might be involved in flax lipid biosynthesis and lipid metabolism. This study is the first to develop InDel markers based on re-sequencing in flax and clustered the markers into two well-separated groups for oil and fibre. The results demonstrated that InDel markers developed herein could be used for flax germplasm identification, genetic diversity analysis, and molecular marker-assisted breeding.


2020 ◽  
Vol 87 (2) ◽  
Author(s):  
Ségolène Calvez ◽  
Nora Navarro-Gonzalez ◽  
Charlène Siekoula-Nguedia ◽  
Catherine Fournel ◽  
Eric Duchaud

ABSTRACT Flavobacterium psychrophilum affects salmonid health worldwide and causes economic losses. The genetic diversity of the pathogen must be considered to develop control methods. However, previous studies have reported both high and low levels of genetic diversity. The present longitudinal study aimed at assessing the genetic diversity of F. psychrophilum at a small temporal and geographic scale. Four farms located on the same watershed in France were studied. Rainbow trout (Oncorhynchus mykiss) batches were monitored, and apparently healthy individuals were sampled over 1 year. A total of 288 isolates were recovered from fish organs (gills and spleen) and eggs. Pulsed field gel electrophoresis revealed high genetic diversity. Multilocus sequence typing performed on a selection of 31 isolates provided congruent results, as follows: 18 sequence types (STs) were found, of which 13 were novel. The mean gene diversity (H = 0.8413) was much higher than that previously reported for this host species, although the sampling was restricted to a single watershed and 1 year. Seven isolates out of 31 were assigned to clonal complex ST10 (CC-ST10), which is the predominant clonal complex in the main salmonid production areas. A split decomposition tree reflected a panmictic population. This finding is important for aquaculture veterinarians in their diagnostic procedure, as the choice of adequate antibiotic treatment is conditioned by the correct identification of the causative agent. Furthermore, this study expands our knowledge on genetic diversity required for the development of an effective vaccine against F. psychrophilum. IMPORTANCE The bacterium Flavobacterium psychrophilum is a serious pathogen in many fish species, especially salmonids, that is responsible for considerable economic losses worldwide. In order to treat infections and to develop vaccines, the genetic diversity of this bacterium needs to be known. We assessed the genetic diversity of F. psychrophilum isolates from apparently healthy rainbow trout raised in several fish farms in the same watershed in France. Two different genotyping methods revealed high diversity. The majority of isolates were unrelated to clonal complex sequence type 10 (CC-ST10), the clonal complex that is predominant worldwide and associated with disease in rainbow trout. In addition, we found 13 novel sequence types. These results suggest that a diverse subpopulation of F. psychrophilum may be harbored by rainbow trout.


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