Agriculturae Conspectus Scientificus, Vol 86, No 2 (2021)

Polymorphisms, Haplotype Variability and Neutrality Test of Bronze Locus in Turkey (Meleagris gallopavo)

Samuel Olutunde DUROSARO, Babatunde Moses ILORI, Oluwaseun Serah IYASERE, Ayotunde Olutumininu ADEBAMBO, Michael Ohiokhuaobo OZOJE

Pages: 183-191


The bronze locus, identified as melanocortin-1 receptor (MC1R) gene, is involved in body coloration. We examined polymorphisms, haplotype variability and deviation from neutrality of bronze locus in Nigerian Indigenous Turkeys (NIT) using British United Turkeys (BUT) as control breed. Single-exon coding region of MC1R was sequenced. Polymorphisms were identified using MEGA v6 and CodonCode Aligner. In silico prediction of the functional effects of amino acid substitutions was done using SNAP2. Haplotypes were reconstructed using DnaSp v5. Eight polymorphisms were identified in MC1R gene of the birds with two novel polymorphisms: c.37C>A (neutral effect) and c.866T>G (gain-of-function) in NIT and BUT, respectively. Mutations c.450C>T and c.866T>G were unique to lavender NIT while c.186C>G was present in all birds. Two polymorphisms, c.866T>G and c.887C>T, were predicted to have functional effects. The highest genetic diversity was observed in lavender NIT while the least was observed in BUT. Fifteen (15) haplotypes were reconstructed, with MC1RBUT1 and MC1RBUT2 unique to BUT. Haplotype MC1R*4 was absent in all the birds used in this study while MC1R*5 was present in all NIT. Our study confirmed that MC1R*2 carried black (B) allele. Two novel haplotypes (MC1RNig1 and MC1RNig2) identified in this study also carried B allele. MC1RNig6, MC1RNig7 and MC1RNig8 were found to be unique to lavender. The novel polymorphisms and haplotypes identified in NIT and BUT could be used in differentiating them from other turkey breeds with the same plumage colours. Also, various polymorphisms and haplotypes identified in bronze locus of turkey are useful in breeding programmes aimed at developing or conserving different plumage colour types.


turkey, B allele, colour, haplotypes, lavender, polymorphisms

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