Transcript Document
a+ --> a- mutation (forward mutation) a- --> a+ reverse mutation (reversion) Presence of pink pigment Amorph Hypomorph Hypermorph Neomorph An ALLELIC SERIES for this gene +/- Animation ed.9: 9.2&9.17 TRANSLATION Animation ed.9: 9.2&9.17 TRANSLATION Now, insertions and deletions of base pairs: Forward mutation Reverse mutation Equivalent reversion UCC (Ser) forward Wild type CGC (Arg, basic) forward Wild type Intragenic suppressor UGC (Cys) Mutant reverse AGC (Ser) Wild type CCC (Proline) reverse CAC (His, basic) Mutant Pseudo-wild type Intragenic suppressor Intergenic suppressor Intergenic suppressor Nonsense suppressor Animation ed9: 9.19a Nonsense mutation Animation ed9: 9.19b Nonsense suppressor Animation 9.19c Nonsense suppression rodns and suppressor-tRNA together give WT phenotype Regulatory Coding Series of slides on molecular markers / genetic mapping (RF) When doing GENETIC mapping, Molecular Markers can be used as a locus Single Nucleotide Polymorphisms (SNPs) AACGTCATCG vs. AACGTTATCG Microsatellites (variable # of short repeats) CGCGCG vs. CGCGCGCGCG vs. CGCG Restriction Fragment Length Polymorphism (RFLP) SNP leading to a loss/gain of a restriction cut site When doing GENETIC mapping, Molecular Markers can be used as a locus Almost all SNPs, Microsatellites, etc. are SILENT, and there are millions of them They are mile-markers, not destinations! ,אבני דרך !ולא יעדים Is there linkage between a mutant gene/phenotype and a SNP? SNP1 SNP1’ USE standard genetic mapping technique, with SNP alternative sequences as “phenotype” ..ACGTC.. B= bad hair, Dominant B 2’ / b 2 ..ACGCC.. SNP2 SNP2’ ..GCTAA.. ..GCAAA.. SNP3 SNP3’ ..GTAAC.. ..GTCAC.. X B/b 1/1’ 2/2’ 3/3’ b/b 1/1 2/2 3/3 B/b 1/1’ 25% 2/2’ 47% 3/3’ 25% B/b 1/1 25% 2/2 3% 3/3 b/b 1/1’ 25% 2/2’ 3% 3/3’ 25% 25% 2/2 47% 3/3 25% b/b 1/1 25% SO…B is 6 cM from SNP2, and is unlinked to SNP 1 or 3 Is there linkage between a mutant gene/phenotype and a SNP? USE standard genetic mapping technique, with SNP alternative sequences as “phenotype” ..ACGTC.. B= bad hair, Dominant SNP1 SNP1’ ..ACGCC.. SNP2 SNP2’ ..GCTAA.. ..GCAAA.. SNP3 SNP3’ ..GTAAC.. ..GTCAC.. X B/b 1/1’ 2/2’ 3/3’ b/b 1/1 2/2 3/3 We have the ENTIRE genome sequence of mouse, so we know where the SNPs are Now-do this while checking the sequence of THOUSANDS of SNPs SO…B is 6 cM from SNP2, and is unlinked to SNP 1 or 3 CGCGCG vs. CGCGCGCGCG vs. CGCG ~1990 Screening for mutations Finding the very rare cases where NEW ALLELES arise • Types of mutations Types of mutations Types of mutations Screening For Mutations + - Screening For Reversions ad- ad+ Neurospora