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Objective Indigenous animals are considered as the national treasures and strategic sources of each country. It is essential to preserve and reproduce them. Since no artificial selection has been employed in Iranian native breeds, there is considerable diversity in their genome. Therefore, having detailed information on the animals' genome can be important for designing breeding plans in the future. The aim of this study was to identify the functional effects of single nucleotide polymorphisms and investigate the genetic diversity in the Khazak chicken ecotype using sequence information of the whole genome. Materials and methods In this study, 17 Khazak chicken samples were sequenced using Next Generation Sequencing (NGS) technique. After preprocessing short sequences using FastQC, Trimmomatic, BWA, Picard software and the GATK program, single nucleotide polymorphisms were identified in GATK program using the UnifiedGenotyper tool. Samtools software was applied to calculate short reads coverage and the percentage of read alignment with the reference genome. The filtering steps of SNPs were performed using Plink software. The genetic diversity within the target population was calculated using the VCFtools program. Results The mean coverage depth for 17 chickens was 6.45. After preprocessing the short sequences, were identified 15,981,176 and 10,552,735 SNPs before and after the quality control, respectively. Functional annotation of the single nucleotide polymorphisms indicated that most of the SNPs are located in the intron and intergenic regions and only 2.8% of them belong to the exon region. The rate of Transition to transversion mutations (Ti / Tv) was 2.43 and the ratio of heterozygous to homozygous SNPs was 3.3 in the Khazak birds, on average. Conclusions The higher number of heterozygous SNPs indicates that there is a high genetic diversity in the Khazak ecotype. Like other Iranian native chickens, the ecotype has the genetic diversity that can be considered a native laying ecotype in the breeding programs. [ABSTRACT FROM AUTHOR]

Objective Evaluation and conservation of native chickens as valuable genomic resources is essential. This is the first study for discovering variants in Lari chicken by whole genome sequencing data. The study of genetic diversity of Lari chicken at genomic level can provide useful information for its preservation and breeding. In this study, genomic diversity of five Lari individuals was investigated using whole genome sequencing technique. Materials and methods Blood samples were taken from five Lari chickens from cites of Shiraz and Zabol, Iran. Whole genome sequencing (paired end sequencing) was done by Illumina Company)Hiseq 2500). Data quality was determined by FastQC program. Whole genome sequencing data were aligned with chicken genome reference (Gallus_gallus-5.0/galGal5) using MEM algorithm applied in burrows wheeler aligner program (BWA). Processing of bam files was done in several steps. PCR duplicates were removed using Picard program. The Percentage of alignment with the reference genome and coverage or depth were calculated using the flagstat and depth commands in samtools software. Single nucleotide polymorphisms (SNPs) and small insertions and deletions (INDELs) were identified by the genomic analysis toolkit (GATK) program. Annotation of SNPs and Indels was done using SnpEff program. Genetic diversity of five chicken genomes was calculated with VCFtools. Results The mean percentage mapping of short sequences with the reference genome was 99.85% and the mean coverage depth was 7.65 X. In this study, 9.8 million SNPs and 10 million Indels were identified with the most counts of them in the intron and intergenic regions. The mean of observed and expected heterozygosity percentages for SNPs in five chicken genomes were 0.30 and 0.35, respectively. Conclusions Results from annotation showed that percentage of silent SNPs (74.38%) is higher than that nonsynomous SNPs (missense and nonsense, 25.62%) in Lari chicken genome. The lower observed genetic diversity than the expected genetic diversity, can be due to the forces such as inbreeding in the population of Lari chicken. The information provided herein can be useful for breed conservation and breeding programs and population structure survey. [ABSTRACT FROM AUTHOR]