High resolution analysis and phylogenetic network construction using complete mtDNA sequences in sardinian genetic...

Area of Science:

• Population Genetics
• Human Evolution
• Mitochondrial Genomics

Background:

• Complete mitochondrial DNA (mtDNA) sequences are optimal for phylogenetic analysis.
• Sardinia's Ogliastra region is known for its isolation and unique demographic history.

Purpose of the Study:

• To sequence the entire mtDNA of individuals from three isolated Ogliastran villages.
• To investigate the genetic diversity and phylogenetic relationships within this isolated population.
• To identify novel genetic variations potentially specific to the Ogliastra region.

Main Methods:

• Whole mitochondrial DNA sequencing (coding and D-loop regions) of 63 individuals.
• Phylogenetic network reconstruction using complete mtDNA sequences.
• Comparison with a large dataset of European mtDNA sequences.
• Calculation of genetic diversity indices.

Main Results:

• Identified 172 coding and 69 D-loop sequence changes, with 13 novel coding region variants.
• Reconstructed phylogenetic networks showing distinct clustering for Ogliastran samples.
• Observed significant genetic isolation and differentiation compared to other European populations.
• Discovered a novel subhaplogroup, U5b3, potentially specific to Ogliastra.

Conclusions:

• The Ogliastran populations exhibit remarkable genetic isolation and differentiation.
• Novel mtDNA variants and subhaplogroup U5b3 may represent unique genetic signatures of the region.
• This study provides valuable insights into the genetic landscape of isolated European populations.