摘要
To investigate the genetic polymorphisms of 19 X‑STR loci in the Han population in Northern China,samples from 628 unrelated individuals(314 males and 314 females)were collected and 19 X‑STR loci were amplified by AGCU X19 STR System.A total of 270 different alleles were detected in 19 X‑STR loci.All loci were in Hardy−Weinberg equilibrium and there was only one pair of linkage loci(DXS10103‑DXS10101).There was no significant difference in allele frequency between male and female populations.The combined power of discrimination in males was 1–1.8667×10−13,while the combined power of discrimination in females was 1–3.6532×10−22.The combined mean paternity exclusion chance(CMEC)for X-chromosomal markers in father/daughter or mother/son duos Mean paternity exclusion chance(MECDesmarais Duo)was 1–5.1109×10−9.Moreover,the CMEC for X-chromosomal markers in trios involving daughters(MECDesmarais)was 1–2.0292×10−12.The compound amplification system composed of 19 X‑STR in this study showed high polymorphism in the Han population of Northern China,which had a high application value in difficult genetic relationship identification.