Identification of genomic regions associated with wool diameter in Iranian sheep breeds

Document Type : Research Paper


1 M. Sc. Student, Department of Animal Science, University College of Agriculture and Natural Resources, University of Tehran, Karaj

2 Associate Professor, Department of Animal Science, University College of Agriculture and Natural Resources, University of Tehran, and Center of Excellence for Improvement of Sheep Carcass Quality and Quantity, Karaj, Iran

3 Assistant Professor, Department of Animal Science, College of Agriculture and Natural Resources, Arak University, Arak, Iran

4 Assistant Professor, Aborayhan, University of Tehran, Pakdasht, Iran


The objective of the present study was to scan the whole genome in sheep for identifying the loci associated with wool diameter. Blood samples were collected from 94 animals, consisting 47 samples per each Lori-Bakhtiary and Zel breeds. Genotyping of samples were performed using Ovine 50k SNP Chip arrays. Quality control filters were applied for the initial genotyping data and 48,056 SNPs belonging to 90 animals were used in the final analysis. The wool samples of these animals were collected and analyzed for the mean fiber diameter and the proportion of fiber that were equal or more than 30 µm using OFDA technology. The fixed effects of herd, birth date and sex were examined and the genome wide association study (GWAS) was performed using PLINK software where FDR correction was used to adjust the error rate. Considering the significant fixed effects in the genomic wide association analysis, three SNPs on chromosomes 1 and 6 (two SNPs) were identified that significantly affect (p<0.05) the trait proportion of fiber equal to or more than 30 µm. Study of genes that had previously been identified in these regions revealed the presence of major genes affecting the quality of wool in these regions.


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