Functions of Taq DNA Polymerase in PCR Reaction

Short Tandem Repeat or STR marker is microsatellite DNA marker occur when short sequence of DNA (1-7)bp repeated adjacent each other in row in genome resulting DNA segments 400 bp in length, (Short= Rang from (1-7)bp in length) (Tandem= Locate adjacent each other at specific locus) (Repeat= Repeat many times in chromosome), STR sequence name by length of repeat unit (Mononucleotide repeats has one nucleotide repeated next to each other in repeat unit) (Dinucleotide repeats have two nucleotides repeated next to each other in repeat unit) (Tri-nucleotide repeats have three nucleotides repeated in repeat unit) (Tetra-nucleotides repeats have four nucleotides repeated in repeat unit) (Penta-nucleotides repeats have five nucleotides repeated in repeat unit) refer to different alleles with different number of repeats, STR marker initiate by DNA extraction and PCR amplification using fluorescent label primers and separate amplified DNA fragment by polyacrylamide gel electrophoresis or capillary electrophoresis to compare bands pattern with known STR profiles, STR marker useful on degraded DNA and consider co-dominant and multiple alleles marker with highly polymorphic nature and stability inheritance on the other hand STR marker have poor bio statistical efficiency leading to possibility observe one or more genetic inconsistencies explained as mutational events, STR marker use in genetic diversity by demonstrating high mutation rates which leading to new alleles within population and DNA fingerprinting and paternity verification and genetic maps and linkage analysis and gene expression studies, STR marker have two types (Autosomal STR provide information about inheritance from parents) (Sex chromosomal STR provide information about inheritance from males or females hence Y-STR marker found in Y chromosome and inherit in block without recombination as haplotype which use for exclusion and paternal lineage analysis (Watch Related Video in #geneticteacher) #geneticteacher