HMB265H1 Lecture Notes - Lecture 4: Mutagen, Indel, Wild Type

• School: UTSG
• Department: Human Biology
• Course: HMB265H1
• Professor: Naomi Levy-Strumpf, Stephen Wright

Document Summary

Hmb265 lecture 3 molecular basis of genetic polymorphisms and their detection. Dna is translated into rna which is needed to generate proteins. Allelic differences at the dna level can influence mrna expression and protein function and therefore affect the phenotype. Mutations can be defined as any change at the level of dna: the creation of entirely new allele can happen. Genes mutate randomly at any time and in any cell within an organism. Mutations can arise spontaneously during cell replication or can be caused by a mutagen: mutagens are frequently used in research. Only mutations in the germline cells can be transmitted onto the progeny: somatic mutations are not passed on. Most genetic variations are created by single nucleotide polymorphism (snps) Wild-type (+) the most common allele (frequency 1%) Mutant allele rare allele (frequency <1%) Mutations which affect the phenotype occur very rarely: most mutations occur in non-coding regions.