Research On Application Of SNP In Discrimination Of Oyster Mushrooms Strains

The confusion and low quality of edible mushroom fungi are two primary problems in China,which have obstacled the development of mushroom industry. We have to launch the identificationof strains to administrate them and to protect the interest of producers. Single nucleotidepolymorphisms (SNP), a new DNA marker, attracts more and more people’s attention. In thisstudy, we studied the relationship between tested strains by analyzing SNPs of five selected genes.In31oyster mushrooms, the dataset included3751bp of sequences: vmh1,418bp; plyA,714bp;PoMTP,1079bp; sdi1,929bp; ste3-like,611bp. There were a total of630polymorphic sites: vmh1,89; plyA,124; PoMTP,132; sdi1,73; ste3-like,212, resulting in an SNP per6bp on average.Among the630SNPs,70sites had three alternative nucleotides,51were In/Del, while theremaining had two each, with382transitions and127transversions, resulting in a combinedtransition to transversion ratio of3:1approximately. Among the coding regions, there were13missense mutations、26synonymous mutations in vmh1,13missense mutations、25synonymousmutations in plyA,27missense mutations、47synonymous mutations in PoMTP,21missensemutations、72synonymous mutations in ste3-like.There are only32synonymous mutations in sdi1coding regions and there are no nonsense mutations in the five genes. The result of clusteringanalysis indicated that there is abundant genetic diversity between31strains and we candistinguish each of them. At last, we selected29SNPs from630SNPs, of which1was in ste3-likefragment10were in plyA fragment and the other18were in PoMTP fragment.31strains could bedistinguished from each other according to the selected29SNPs.In8Pleurotus pulmonarius, the dataset included1013bp of sequences: vmh1,414bp;ste3-like,599bp. There are a total of162polymorphic sites: vmh1,31; ste3-like,131, resulting anSNP per6bp on average. Among the162SNPs,12sites had three alternative nucleotides,12wereIn/Del, while the remaining had two each, with94transitions and40transversions, resulting in acombined transition to transversion ratio of2:1approximately. Among the coding regions, therewere10missense mutations、10synonymous mutations in vmh1,14missense mutations、36synonymous mutations in ste3-like. There are no nonsense mutations in two genes. We also select-ed16SNPs from162SNPs. They were in ste3-like fragment.8strains could be distinguished from each other according to the selected16SNPs. The result of clustering analysis (includingstrain00649) indicates that there is abundant genetic diversity between9strains and we candistinguish each of them. As a result, we can draw a conclusion that SNP marker could be used todistinguish strains.