Comments on the paper entitled "Polymorphism of nine X chromosomal STR loci in Koreans" by Jin Young Son et al. (2002) Int J Legal Med 116:317?321

Abstract

Dear Sir,We highly appreciate that more and more forensic research groups are focusing their attention on the X chromosome (ChrX) to increase the number of established ChrX markers. We therefore read the paper by Jin Young Son et al. (2002) with great interest, however we find it difficult to agree with them on several points.The authors suggest that the allele distributions in the Korean sample do not differ from those of other populations, and cite our investigations in Europe with reference to DXS6789 (Hering et al. 2001) and DXS9898 (Hering and Szibor 2000). However, the results obtained by Jin Young Son et al. (2002) do seem to show considerable differences to our findings, e.g. for DXS9898 we found the allele 8.3 on about 25% of the chromosomes examined in Germany but for the Korean publication the allele 8.3 is not described. We established a frequency of about 16% for the allele 13, whereas the Korean colleagues indicate a frequency of 1%.Discrepancies can be also found in other loci, such as DXS6789, DXS7133, DXS7132, DXS8378, etc. (Edelmann et al. 2001), and as they are obvious we do not consider it necessary to prove them by means of a statistical method. As no reference is given to the use of any international standard DNA, such as K562 or 9947A, it cannot be verified whether the allele designation as suggested corresponds to that of other publications.