Table 10.

Classification of mtDNA variation in highland and lowland chickens

Population	SNV	Insertion	Replacement	Total	New variants	Coding variants	Amino acid changes
Highland-male	21	1	1	23	23	14	5
Highland-female	9	0	0	9	8	4	1
Lowland-male	8	0	0	8	8	6	2
Lowland-female	10	0	0	10	10	7	2

In this study, mtDNA variants were analyzed, separately. After variants calling, all mtDNA variants including SNV, insertion and replacement were obtained from highland and lowland chickens, separately. Filtrations were also carried out same as what described for differential variants. We recognized that highland chickens had more variants than lowland chickens (32 versus 18 variants). It might be explained that more variants in highland chickens were created in order to adapt to the high-altitude conditions.

Novel variants: variants were reported for the first time.

Coding variants: variants were located on coding regions.

Amino acid changes: The protein sequence can be changed by the variations.