The Characteristics of Microsatellites and Development of SSR Markers in the Genome of Periplaneta americana

Abstract

The research was to analyze the number and pattern of microsatellites in Periplaneta americana’s genome, and also developed tetranucleotide SSR markers. We thoroughly scrutinized and dissected the inherent traits that govern the allocation of microsatellite sequences within the profound domain of P. americana’s genome, software MSDBv2 allowed for the utilization of 2.67 Gb. There were precisely 1,498,458 flawless microsatellite sequences, encompassed approximately 1.57%. The cumulative length of microsatellites was 45,076,707 bp, and the abundance of microsatellites was 16889.577 loci/Mb. Out of all the microsatellite repeat variations, the trinucleotide repeats accounted for 44.83% of the total, with a count of 671,830, which were the most abundant type. The tetranucleotide, mononucleotide, pentanucleotide, dinucleotide, and hexanucleotide repeats accounted for 29.01%, 13.62%, 8.37%, 3.70% and 0.47%, respectively. The numbers of different repeat copy categories in each repeat type were also quite different, such as the A in mononucleotide repeat type, the AT in dinucleotides, the AAT in trinucleotides, and AAAT in tetranucleotide were the most of each categories. 143 primers were designed. After undertaking the arduous task of enhancing the initial PCR conditions to perfection, we successfully determined and analyzed a gargantuan number of 38 different polymorphic tetranucleotide microsatellite markers with utmost precision, employed the assistance of two-color fluorescence markers and ingenious genotyping scaned for their comprehensive characterization. The genetic variation in P. americana population involved analyzing the diversity of microsatellite loci, which exhibited varying numbers of alleles per locus ranging from 4 to 21 among the 32 individuals studied. Among them, there were 24 microsatellite loci whose alleles were greater than 10, accounted for 63.16% of the total number of polymorphic microsatellite. The calculated degrees of genetic diversity varied between 0 and 1, the observed heterozygosities was between 0.219 and 1.0, with a mean of 0.6391. The expected heterozygosities was between 0.312 and 0.942, with a mean of 0.7663. The PIC was between 0.296 and 0.923, with a mean of 0.7294, and there were 36 microsatellite loci whose PIC was greater than 0.5, accounted for 94.74%. This study indicated that new development of microsatellite markers for P. americana was feasible. Furthermore, these new development microsatellite markers will provide adequate and reliable molecular genetics data for carrying out the research of molecular ecology and conservation genetics for P. americana.