Ancient spice route may have shaped Keralam’s Malabari goat’s genetic legacy, study shows

Keralam’s ancient maritime connections may extend beyond spices, merchants and ports. A new study suggests that these trade networks may also have shaped the maternal genetic history of the Malabari goat, one of the State’s iconic indigenous breeds.

Researchers from the Kerala Veterinary and Animal Sciences University (KVASU) have reported the first complete mitochondrial genome of the Malabari goat. The findings, published in the peer-reviewed journal Mammalian Genome, provide molecular evidence supporting the possibility that goats moved along the historic Indian Ocean Spice Route, linking the Malabar Coast with western India and the Arabian Peninsula.

Native to South Malabar, the Malabari goat is valued for its milk and meat and its ability to thrive in Keralam’s hot and humid conditions. Historical accounts have suggested that the breed developed through contributions from Arabian, Mesopotamian, Surti and local feral goat populations.

Researchers analysed whole-genome sequencing data from 20 unrelated female Malabari goats from Kannur, Kozhikode, Wayanad, Palakkad, Thrissur and Malappuram. They identified 45 single-nucleotide polymorphisms and two insertion-deletion variations in the mitochondrial genome, which contained 37 genes and a hypervariable D-loop region.

Mitochondrial sequence identity

The Malabari goat showed its highest mitochondrial sequence identity, 99.7%, with Meriz goats from Iraq. It also showed close maternal genetic relationships with goats from Oman, Arabia and Gujarat.

“Malabari goats belong to a rare maternal genetic group found in only about 3% of domestic goats globally. Also found in Omani and Surti goats, the lineage traces back to wild Bezoar goats of present-day Iran and Iraq. The shared ancestry among goats from Keralam, Gujarat, Oman and Iraq suggests that ancient Indian Ocean maritime trade likely played a role in their movement,” said M. R. Akhila, co-author and research scholar.

The goats were placed in mitochondrial haplogroup B1, a relatively uncommon lineage among domestic goats. The researchers said Surti goats of Gujarat also belong to haplogroup B, while B1 has been reported among Omani goats.

Marykutty Thomas, co-author and assistant professor at the Centre for Advanced Studies in Animal Genetics and Breeding, KVASU, said the findings indicate a shared maternal ancestry among goat populations in Keralam, Gujarat, Oman and Iraq.

The study also identified a novel mutation in the MT-TL2 gene, described by the researchers as the first mitochondrial tRNA mutation reported in goats.