MCB 2400 Lecture Notes - Lecture 9: Alec Jeffreys, Tandem Repeat, Variable Number Tandem Repeat
15 Dec 2016
School
Department
Course
Professor
Sir Alec Jeffreys
• father of DNA figerpritig
o DNA can serve as a unique identifier
• Monday September 10th, 1984 → eureka
• Research:
o Gene evolution in sparrows
o Repetitive sequences in human myoglobin gene
• Found:
o Human genome contains many regions of hypervariable DNA
o Can serve as a unique identifier
Two Major Types of DNA Markers: mark sequence as difference from another sequence
• Sequence polymorphism:
o Single nucleotide polymorphism, SNP
▪ --------AGACTAGACATT-------
▪ --------AGATTAGGCATT-------
• Length polymorphism:
o Short tandem repeat, STR
o Variable number tandem repeat, VNTR hat Jeffres as studig
▪ ---------(CAG)(CAG)(CAG)----------
▪ ---------(CAG)(CAG)----------
Minisatellite (VNTR) vs. Microsatellite (STR)
• PCR primers are designed to target invariant flanking sequence regions
• The number of tandem repeat units in the repeat regions varies among individuals making them
useful markers for human identification
Withi seods it as oious that e had stuled upo a DNA-based method not only for biological
idetifiatio, ut also for sortig out fail relatioships. It reall as a etraordiar oet.
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Two major types of dna markers: mark sequence as difference from another sequence: sequence polymorphism, single nucleotide polymorphism, snp. Length polymorphism: short tandem repeat, str, variable number tandem repeat, vntr (cid:894)(cid:449)hat jeffre(cid:455)(cid:859)s (cid:449)as stud(cid:455)i(cid:374)g(cid:895) What do (cid:449)e k(cid:374)o(cid:449) fro(cid:373) jeffre(cid:455)(cid:859)s vnt studies: human genome contains many regions of hypervariable dna (vntr sequences, can serve as a unique identifier, genetic markers that differ between humans = polymorphisms. Pcr (today, much easier: looks at strs, use pcr amplification of specific tetra nucleotide repeat sequences. Allele locus: locus = particular position or location on a chromosome, allele = alternate sequence at a particular locus, homologous pair, same characteristic but different versions of gene or locus. Genotype designations (allele state: aa, homozygous dominant, aa, heterozygous, aa, homozygous recessive, genotypes can represent genes, genotypes can represent alleles for non-protein coding segments for the dna, strs.
