Login

Join for Free!
119317 members


Nucleotide sequences

Genetics as it applies to evolution, molecular biology, and medical aspects.

Moderator: BioTeam

Nucleotide sequences

Postby Deat » Tue May 10, 2011 11:09 am

Can someone help to explain some things to me, I dont understand the notes and I think someone wording it differently may help me to understand it, plus someone who answers in english rather than cryptic. (I have it on good sources my biology teacher isnt the only one who does this) I need these definitions for AS level biology.

Fragment length polymorphisms
microsatellite repeat sequences
single nucleotide polymorphisms.
Deat
Garter
Garter
 
Posts: 8
Joined: Wed Nov 17, 2010 11:58 am

Postby Babybel56 » Tue May 10, 2011 7:11 pm

Fragment length polymorphisms: two stretches of nucleic acid that are the same except for the locations of restriction sites. So as a whole they function the same, but when restriction enzymes are used to cut them up different fragments are created.

Microsatellite repeat sequences: also known as short tandem repeats (STRs) these have a high mutation rate and are used for mapping populations as genetic markers. They're just repeating sequences of a small number of base pairs (1-6).

SNPs: these are differences of a single nucleotide in a genome between a pair of chromosomes in an individual, or between two members of a species. They're responsible for the individuality of each...well, individual.
Babybel56
Death Adder
Death Adder
 
Posts: 65
Joined: Mon Apr 18, 2011 11:35 am
Location: University of Cambridge, UK

Postby JackBean » Wed May 11, 2011 6:09 am

I would correct the SNPs, they are considered SNP, if they are located at least in 1% of the genes of population ;)
Also, the STRs are changing in the length, not sequence (you just didn't specify that)
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.
User avatar
JackBean
Inland Taipan
Inland Taipan
 
Posts: 5692
Joined: Mon Sep 14, 2009 7:12 pm


Postby Deat » Fri May 13, 2011 1:50 pm

Can I ask with fragment legnth polymorphisms, why do you get different sized fragments when you cut them with a restriction enzyme like EcoR1
Deat
Garter
Garter
 
Posts: 8
Joined: Wed Nov 17, 2010 11:58 am

Postby JackBean » Sun May 15, 2011 6:32 pm

if there is a sequence which either contain or does not contain a restriction site, you get one pattern, but if it mutates, then you get different pattern, because of the extra/missing restriction site ;)
http://www.biolib.cz/en/main/

Cis or trans? That's what matters.
User avatar
JackBean
Inland Taipan
Inland Taipan
 
Posts: 5692
Joined: Mon Sep 14, 2009 7:12 pm


Return to Genetics

Who is online

Users browsing this forum: No registered users and 2 guests