The Karimojong from Uganda: genetic characterization using an X-STR decaplex system

Area of Science:

• Forensic Genetics
• Population Genetics
• Human Identification

Background:

• The Karimojong people of Northeast Uganda represent a distinct African population group.
• Understanding the genetic diversity within populations is crucial for forensic science and anthropological studies.
• Short tandem repeats (STRs) on the X chromosome (X-STRs) are valuable genetic markers for human identification.

Purpose of the Study:

• To genetically characterize the Karimojong population using a panel of ten X-STR loci.
• To evaluate the forensic efficiency of these X-STR markers in this specific population.
• To assess the utility of X-STRs for parentage testing and human identification within the Karimojong.

Main Methods:

• Genotyping of 255 individuals (117 males, 138 females) from the Karimojong population.
• Analysis of ten X-STR loci: DXS8378, DXS9898, DXS7133, GATA31E08, GATA172D05, DXS7423, DXS6809, DXS7132, DXS9902, and DXS6789.
• Calculation of allele frequencies, gene diversities, and forensic parameters (e.g., power of discrimination, power of exclusion).

Main Results:

• The DXS6789 locus exhibited the highest polymorphism (84.79% gene diversity), followed by DXS6809 (83.94%).
• The DXS7133 locus showed the lowest discrimination power (39.79% gene diversity).
• High overall power of discrimination was observed for both female (1 in 1.8 x 10^10) and male (1 in 1.6 x 10^6) samples, alongside high power of exclusion in trio and duo cases.

Conclusions:

• The ten X-STR loci analyzed are highly informative for the Karimojong population.
• This X-STR panel demonstrates significant potential for accurate parentage testing and individual identification in forensic investigations involving the Karimojong.
• The findings contribute valuable genetic data for African populations and enhance the application of X-STRs in forensic genetics.