VNTRs repeated units

Minisatellites-the repeated unit typically ranges from 20 to 70 bp, and the length of the entire repeat may reach 20 kb. This is the class most often referred to as VNTRs and contributes to RFLP patterns on Soulhem blots. 

VNTRs (variable number of tandem repeats). These polymorphisms are the result of varying numbers of minisatellite repeats in a specific region of a chromosome. The repeat units typically range in size from 20 to 70 bases each. The repeat is flanked on both sides by a restriction site, and variation in the number of repeats produces restriction fragments of varying size. 

Pattern of fragments varies from one person to another according to where and how many repeated units of the VNTR are located on their genomes, —i—— J... 

There are several major types of DNA sequence variation in the human genome. One type comprises repeated sequences with variations in the number of repeat units, such as short tandem repeat polymorphisms (STRPs, also known as microsatellites) in the form of mono-, di-, tri-, and tetra-nu-cleotide repeats, or more complex sequence repeats such as variable number tandem repeats (VNTRs) [2-4]. Repeat polymorphisms are relatively... 

Variable numbers of randomly repeated (VNTR) units are one common type of insertion that results in an RFLP. The VNTRs can be inherited, in which case they are useful in estabhshing genetic association with a disease in a family or kindred or they can be unique to an individual and thus serve as a molecular fingerprint of that person. 

The initial VNTRs were several hundred nucleotide units long requiring extended laboratory periods for the various segments to separate on the gel. Today, most tests employ shorter, 3 5 nucleotides long, VNTRs that allow for more rapid movement on the gel, resulting in faster and less costly results. It also allows for the production of a greater number of sequences that are looked at, and hence a greater ability to match or not match the results. These shorter sequences are called short tandem repeats (STRs). 

TNF TNP TNP-OVA tRNA TSH TSHR tTG HP UN UNEP VNTR WHO XLA tumour necrosis factor trinitrophenol trinitrophenol-ovalbumin transfer ribonucleic acid thyroid-stimulating hormone thyroid-stimulating hormone receptor tissue transglutaminase thrombotic thrombocytopenic purpura United Nations United Nations Environment Programme variable number of tandem repeats World Health Organization X-linked agammaglobulinaemia... 

---