Arch Hellen Med, 20(5), September-October 2003, 519-525
Determination of sibship by DNA analysis in Greeks
Α. ΚOUVATSI,1 P. DELIGIANNIDIS,1
L. FLORENTIN,2 A. TRIANTAFYLLIDIS,1
OBJECTIVE In cases where there is no parental DNA sample, a sibship determination is possible via specific DNA analysis. The aim of this study was to validate the efficiency of kinship analysis in the Greek population using several unlinked autosomal STRs, which are characterized by high degree of polymorphism and heterozygosity values.
METHOD 14 couples of true full-siblings and 54 couples of random Greek individuals were analyzed for 10 STRs. The combined sibship index (GSI) was estimated from the results obtained. Finally, a sibship analysis was performed in four cases.
RESULTS The GSI value ranged from 0.6 to 474,376 for the full-sibling couples and it was not greater than 1 for the 54 random population couples. A GSI value of over 30 is considered to be a strong indication in favor of sibship. Another strong indication is the fact that the two individuals share both alleles (and not only one of them) in a STR marker. A sibship relationship was certified in three out of the four cases.
CONCLUSIONS The results of this research may prove useful in forensic laboratories where missing identity cases and kinship analyses are performed. The analysis of at least 16 unlinked autosomal STRs is recommended for trustworthy results. In some cases sequencing analysis of the mitochondrial DNA or Y-STR analysis is required.
Key words: DNA analysis, Kinship, Siblings.