Variable Number Tandem Repeat Lab Report

A Variable Number Tandem Repeat (VNTR) is a molecular motif that plays a considerable role in molecular genetics and specifically forensic analysis [1]. The goal of this experiment is to observe the tandem repeats of the VNTR (D1S80) locus through molecular lab techniques. Cheek cells were isolated from an individual and amplified via a polymerase chain reaction (PCR). Then, the amplified sample was separated through gel electrophoresis. This project entails the interpretation of fluorescing bands from gel electrophoresis in order to determine the number of tandem repeats present on an individual’s alleles. The total number of tandem repeats is expected to fall between the experimentally observed range of 21 and 33 repeats [4]. The results show that the individual’s D1S80 genotype was successfully calculated through measurement of the gel electrophoresis bands and this subject’s D1S80 genotype of (22,32) indeed falls between the predicted 21 and 33 repeats. Additionally, the implications of this experiment suggest an aspect of reproducibility as well as convenience concerning the measurement of tandem repeats within VNTR loci. High variation between compared subjects’ results can be explained through various population-genetic factors. [3,5] …show more content…
A VNTR consists of a number of repeating DNA sequences, often a result of an uneven chromosome crossover or DNA replication slippage [6]. An individual’s VNTR loci exhibit considerable variation due to inheritance of alleles from each parent, and thus VNTR loci have been widely used for forensic fingerprinting and analysis [1]. Additionally, VNTR loci have been linked to a predisposition to certain diseases [2]. The wide use of VNTR in molecular biology is not only an indication of convenience but also