An improved method of mismatching polymerase chain reactionrestrictive fragment length polymorphisms(PCR-RFLP) was performed in our lab for genetic diagnosis of spinal muscular atrophy(SMA). PCR amplification and rest...An improved method of mismatching polymerase chain reactionrestrictive fragment length polymorphisms(PCR-RFLP) was performed in our lab for genetic diagnosis of spinal muscular atrophy(SMA). PCR amplification and restriction endonuclease digestion of exons 7 and 8 permit distinction of the telomeric survival motor neuron (SMN) gene and its centromeric copy. Lack of a PCR product from either exon and from either gene is indicative of homozygous deletion of that sequence, and a high correlation with clinical SMA. Our data showed: 9 cases in 10 presumed SMA children were positive, i.e. deletion of telomeric SMN gene. One case was negative. 20 cases of normal familial members and 20 cases of normal health persons were all negative. Our results matched the criteria and reports of foreign countries. The method we used is highly specific, sensitive and reliable and is suitable for genetic diagnosis of SMA and its prenatal diagnosis.展开更多
Objective To further define the extent of chromosome 9p21 deletion in periampullary neoplasms.Methods The loss of heterozygosity at 5 microsatellite polymorphic markers on chromosome 9p21 was detected by polymerase ...Objective To further define the extent of chromosome 9p21 deletion in periampullary neoplasms.Methods The loss of heterozygosity at 5 microsatellite polymorphic markers on chromosome 9p21 was detected by polymerase chain reaction (PCR), polyacrylamide gel electrophoresis (PAGE) and silver staining in 35 specimens of periampullary neoplasms and their matching blood samples.Results Fifty percent (4/8) of pancreatic cancer cases showed the loss of heterozygosity at one or more microsatellite loci, with the more frequent sites of D9S974 (37.5%) and D9S942 (28.6%), and some showing consecutive allelic loss. Sixty-two point five percent (5/8) of ampullary carcinoma cases showed loss of heterozygosity at one or more of the loci, frequent site of loss being D9S942 (42.9%) and the next most frequent being IFNA (37.5%) and D9S171 (37.5%). Loss of one locus was observed in 14.2% (1/7) of insulinoma. Conclusion The minimal common region of chromosome deletion in periampullary neoplasms is defined between the D9S974 and D9S942 loci within a 15?kb interval in 9p21, suggesting the involvement of a novel tumor suppressor gene in their carcinogenesis.展开更多
文摘An improved method of mismatching polymerase chain reactionrestrictive fragment length polymorphisms(PCR-RFLP) was performed in our lab for genetic diagnosis of spinal muscular atrophy(SMA). PCR amplification and restriction endonuclease digestion of exons 7 and 8 permit distinction of the telomeric survival motor neuron (SMN) gene and its centromeric copy. Lack of a PCR product from either exon and from either gene is indicative of homozygous deletion of that sequence, and a high correlation with clinical SMA. Our data showed: 9 cases in 10 presumed SMA children were positive, i.e. deletion of telomeric SMN gene. One case was negative. 20 cases of normal familial members and 20 cases of normal health persons were all negative. Our results matched the criteria and reports of foreign countries. The method we used is highly specific, sensitive and reliable and is suitable for genetic diagnosis of SMA and its prenatal diagnosis.
文摘Objective To further define the extent of chromosome 9p21 deletion in periampullary neoplasms.Methods The loss of heterozygosity at 5 microsatellite polymorphic markers on chromosome 9p21 was detected by polymerase chain reaction (PCR), polyacrylamide gel electrophoresis (PAGE) and silver staining in 35 specimens of periampullary neoplasms and their matching blood samples.Results Fifty percent (4/8) of pancreatic cancer cases showed the loss of heterozygosity at one or more microsatellite loci, with the more frequent sites of D9S974 (37.5%) and D9S942 (28.6%), and some showing consecutive allelic loss. Sixty-two point five percent (5/8) of ampullary carcinoma cases showed loss of heterozygosity at one or more of the loci, frequent site of loss being D9S942 (42.9%) and the next most frequent being IFNA (37.5%) and D9S171 (37.5%). Loss of one locus was observed in 14.2% (1/7) of insulinoma. Conclusion The minimal common region of chromosome deletion in periampullary neoplasms is defined between the D9S974 and D9S942 loci within a 15?kb interval in 9p21, suggesting the involvement of a novel tumor suppressor gene in their carcinogenesis.
