A region of the D17S30(pYNZ22) locus was amplified in DNA from 120 unrelated chinese individuals was carried out. The amplified products were analysed by mini-polyacrylamide gel electrophoresis followed by silver stain. 11 alleles, ranging from 170bp to 870bp in size and from 0. 4 % to 30. 4 % in frequency, was detected. The heterozygosity was 73%, Dp value was 0.938. The family study showed that the Amp-FLP in pYNZ22 locus is inherited according to the Mendelian law. The correct genotyping results can be obtained from very little amount of biological material, such as mixed stains, blood stains, single hair and saliva.

The polymorphisms of minisatellite p33.6 (D1S111) locus were typed rapidly and accurately us- ing polymerase chain reaction (PCR). The amplified fragments were analyzed by mini- polyacrylamide gel electrophoresis followed by silver stain. The distribution of allele frequencies among 100 unrelated Chinese is reported. 14 alleles, containing 9 to 22 repeat units, had been detected with a heterozygosity of 76%. The allele frenquencies were from 0.5 %to 35.5 %. The size of amplified fragments ranged from 435 bp to 925bp. The discrimination power of p33.6 locus was 0. 916. The Amp --FLP was inherited according to the Mendelian Law. The results showed that the polymorphisms of p33.6 locus can be used for individual identification and paternity test.

DNA extracted from 100 unrelated Chinese were detected by using the Polymerase Chain Reaction (PCR), mini polyacryl gel vertical electrophorese and silver staining techniques at the p33. 4 locus. Among 100 unrelated individuals, 8 alleles were detected,Foster-Freeman BIOTRAC system indicated that the number of copies of the tandem repeats in different allele was 7, 10 to 15 respectively.There was a rare allele whose copy number was more than 13 but less than 14. The allele fragmehtlength varied from 603 to 1115bp,the allele freqency 0.5 % ~ 53. 5 %,heterozygosity 64 %,DP value84. 5 %. Pedigree analysis indicated that alleles of p33. 4 locus obey Mendel's Laws. Successful typingof various tissues and single hair folicle had confirmed that this technique is suitable for personal identification. In addition, by using Chelex we had established an alterntive method for extracting DNAfrom biological materials,whlch is rapid and easy to perform.

Objective To explore the contribution of ultrasonic examination and localization in early breast cancer screening of chinese women with dense breast.Methods From February,2002 to April,2006,the breasts of 5 000 women were examined using ultrasonic examination,and in about 4 000 women a mass was detected,which included 142 cases of breast cancer proved by pathology with diameter ≤2cm occurred in patients with dense breast.In these parients,ultrasonic visualization and molybdenum target mammographic were performed.Results In these with breast cancer and dense breast,there were 47 cases(33.10%) with microcalcification detected by ultrasonography,the sensitivity rate was 74.60% and the accuracy rate was 88.73%.Only 38(26.76%) cases were detected by mammography,the sensitivity rate was(60.32)% and the accuracy was 82.39%.About 44.37% breast cancer with dense brast display as the(microcalcification).There were 110 cases(77.46%) of the small breast cancer detected by ultrasonography,the sensitivity was 88.71% and the accuracy rate was 90.14%.There were 100 cases(70.42%)(detected) by mammography,the sensitivity rate was 80.65% and the accuracy rate was 83.10%.Also,in 12 patients an unpalpation breast lesion was correctly excised by the use of ultrasonic localization.(Conclusions)(1)For the small breast cancer in dense breast the sensitivity and the accuracy of ultrasonography(surpassed) those of mammography.(2)The ultrasonic examination is an effective way for early breast cancer screening in young women with dense breast and flat breast.Ultrasonography can improve the rate of dignosis in early breast cancer,and also improve the breast-conserving surgical rate.Ultrasonography is worth of widespread use spreading.