Relationship Between The Mutations Of Leptin Receptor Gene And Breast Cancer

ObjectiveThis study is done to investigate the relationship between the variations of leptin receptor gene exon 4, exon 6, exon 9, exon 20 and breast cancer, and to identify the candidate genes and the protecting genes.Material and methodsGenomic DNA was extracted from focus and para-focus tissue venous and blood samples which taken from 46 breast cancer patients,15 benign patients , extracted from blood samples taken from 60 controls from the same population.The genotypes of leptin receptor gene exon 4, exon 6, exon 9, exon 20 were examined with PCR amplification and direct sequence analysis,restriction fragment length polymorphisms(PCR- RFLPs) technique, semi-nested PCR amplification and restriction fragment length polymorphisms (snPCR- RFLPs),PCR-single strand conformation polymorphism analysis(PCR- SSCP).Results1. Nucleotide substitutions occurred at relatively high frequencies at exon 6, 9, 20 (80, 15, and 100%, respectively).2. Genotype frequency of Gln223Arg determined by PCR-RFLP analyses showed no significant differences between controls and cancer groups or between benign and cancer groups(χ2=3.796,P=0.704),so did allele frequency of A and G(χ2=1.959,P=0.581).3. Genotype frequency of Pro1019Pro determined by smPCR-RFLP analyses showed significant differences between groups , allele frequency of A and G showed no significant differences between benign and cancer groups; but significant differences between cancer groups and controls(P<0.05).4. Ala976Asp variant was found in all subjects; no mutations were found in exon 4.5. Genotype frequency of Ser343Ser determined by PCR-SSCP analyses showed no significant differences between between controls and cancer groups or between benign and cancer groups(χ2=6.891,P=0.903),so did allele frequency of A and G(χ2=1.959,P=0.581).ConclusionsOur finding suggests that there was no relationship between the variations of leptin receptor gene Ser343Ser, Ala976Asp, Gln223Arg, Pro1019Pro and breast cancer.