The first mitochondrial survey on the current population of the Maltese cattle breed testifies a strong and significant founder effect and a maternal influence from Northern Europe

Abstract

Local breeds represent an important and often unique pool of endangered sources of genetic variability, particularly when confined to an isolated geographic area. The Maltese breed of cattle is considered to be of ancient origin. Late Pleistocene Oxen skeletal remains and Neolithic representations of primitive cattle have been suggested as proof of a possible local domestication. The objective of the present study is to explore the current mitochondrial DNA (mtDNA) diversity of this breed in order to reconstruct its maternal origins and to identify any residual genetic variants to be preserved. A mtDNA control-region analysis performed on the entire Maltese cattle population identified only two different mtDNAs (out of a total amount of 19 samples), one encompasses about 90% of the current population and confirms a strong founder effect on the mitochondrial gene pool; the remaining 10% seems to testify for the importation of British cattle, documented in historical records since 1809. The complete mtDNA has defined two novel clades T3c and T3d, both dated to ~9.5 thousand years ago, encompassing the Maltese breed and only a few other breeds of Northern European ancestry. This new piece of information does not support the hypothesis of a local domestication in Malta since the Maltese cattle mtDNAs are nested within the known domestic founding lineage T3, but confirms a strong maternal influence from Northern Europe rather than from the African coastline.