Conclusion:B oth polymorphism and heterozygosity of STR 4A, 9A and 9B are high in normal cont rols and in CMT1 patients. Especially 9A and 9B have the highest observed hetero zygosity reported to date for CMT1A markers. They are the ideal markers to detec t CMT1A gene duplication clinically.
Method Polymerase chain reaction(PCR) combined with restriction enzyme digestion and amplification of short tandem repeat (STR) sequence were used to detect gene duplication on chromosome 17p11.2～12 in 30 CMT1 patients and 10 CMT2 patients coming from unrelated families.
Based on new materials and methods,this paper analyses the tandem and segmental duplication,then estimates the num of the lost gene after gene duplication in the Arabidopsis gene family,and we find an evidence for the whole genome duplication in Arabidopsis which happened about 80 million years ago.