| ObjectiveAsthma is a kind of Chronic inflammation that eosinophils and mast cells and T cells participate in. Asthma is characterized by structural remodeling of the airway wall and nonspecific bronchial hyperre-sponsiveness that is caused by Chronic inflammation.Although environmental influences are important in the development of asthma, there is a strong genetic predisposition. Many studies by affected sibling and familes identified aggregation of asthma. Through gene scan people have found some genes and loci on chromosomes linkage with asthma, supporting the polygenic nature of asthma. The susceptibility of asthma is controlled by some genes and every gene has its role on it .Recently people identified many susceptible genes of asthma through gene scan and linkage study. Because IL -4 and IL - 13 play a great role in the development of asthma their genes are considered as important candidate genes of asthma. IL - 4 and IL - 13 both act on IL -4Ra,so IL -4Ra plays a critical role in the development of asthma. Its gene is considered as important candidate gene of asthma.Cytokines are important in the development of inflammation of asthma. Chemokines are one kind of them. The C - C chemokines are the subgroup of it. Chemokines have important relation with asthma. Recently a 32 - bp deletion in the CCR5 has been described. TheCCR5A32 mutation may be relevant to asthma.To investigate the real gene of asthma we examine the relation between Q576R IL -4 receptor a allele or CCR5A32 mutation and asthma among the Han nationality people in the north of China.Materials and MethodsWe take DNA from peripheral blood of asthmatic families and healthy controles as materials. We extract DNA from peripheral blood of asthmatic families and healthy controles as materials by phenol/ chloroform. We amply PCR by the primers of Q576R IL -4 receptor a allele . The PCR product is 209 bp. If the genotype is R576 it can be divided into two fragments of 186bp and 23 bp by Pvu 1 enzyme . If the genotype is Q576 it cannot be divided . We amply PCR by the primers of CCR5A32. The PCR product is 276 bp. If the genotype is CCR5A32 the PCR product is 244 bp. We can determine the genotypes by gel electrophoresis. The comparision way of the allele frequencies is X2 test. If p <0. 05 the discrepancy is significant.Results1. Q576R IL -4 receptor ct allele209 bp fragment product is obtained both in asthmatic family group and healthy control group. QQ indicates wild type, QR indicates mutant heterozygote, RR indicates mutant homozygote. The distribution of genotypes in asthmatic family group is : RR 2.13% ,QR 17. 02% , QQ 80. 85% ; the distribution of genotypes in asthma patient group is: RR 2.86% ,QR 20% ,QQ 77.14% ; the distribution of gen-otypes in healthy control group is: QR 16% ,QQ 84%. The distribution of allele frequency in asthmatic family group is-. R 10. 64% , Q 89. 36% ; the distribution of allele frequency in asthmatic patient group is: R 12. 86% ,Q 87. 14% ; the distribution of allele frequency in healthy control group is : R 8% , Q 92%. There is no significant discrepancy between the allele frequencies of asthmatic family group and healthy control group. There is no significant discrepancy between the allele frequencies of asthmatic patient group and healthy control group.2. CCR5The PCR products are both 276 bp in asthmatic family group and healthy cotroll group. We havent found CCR5A32 mutation.DiscussionPeople determine that asthma is a kind of complex polygene inherited disease through gene scan and candidate gene technique in the past 20 years. Both envirmental facor and genetic susceptibility have their effect on the development of asthma. The investigations indicate that some loci on some chromosomes are relevant to asthma. There are some candidate genes for asthma on 5q mainly on 5q31 -33. There are leucocyte antigen gene and TNF gene on 6p and they are the candidate genes for asthma. Some candidate genes for asthma locate on 11,12,14,16,17,19 chromosomes too. But there... |
PDF Full Text Request