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Biology-Related Homework Help Cell Biology Topic started by: RobinStaleman on Jun 20, 2023



Title: VNTR D1S80
Post by: RobinStaleman on Jun 20, 2023
Hi,
I have a question about the VNTR D1S80. if you put it on the gelelektrofores you have a repeat unit of 16 basepairs. But why is that.
If you look at another VNTR, take VNTR D17S30, the repeat unit is 70 base pairs.


Title: Re: VNTR D1S80
Post by: cmt0730 on Jun 21, 2023
Hi!

Gel electrophoresis works by separating molecules based upon charge, size and shape. In the case of VNTR D1S80, the repeat unit is 16 base pairs long. This means that the sequence of nucleotides repeated in tandem within this VNTR locus consists of 16 base pairs. The variations in the number of repeat units, which may range from a few to several dozen, result in different-sized alleles on gel electrophoresis. On the other hand, VNTR D17S30 has a repeat unit of 70 base pairs. The DNA sequence within this VNTR locus contains a different set of nucleotides repeated in tandem, with each repeat unit consisting of 70 base pairs.


Title: Re: VNTR D1S80
Post by: bio_man on Jun 22, 2023
What do you mean by "But why is that."?

According to the following article (https://www.minipcr.com/wp-content/uploads/KT100901_miniPCR_D1S80_instructor_guide_V2.2_041322.pdf):

D1S80 is a VNTR region located on human chromosome 1 and consists of a 16-base pair-long repeat unit. Most people have between 14 and 41 copies of this repeat, resulting in D1S80 alleles with repeat regions of 224 to 656 base pairs in length.