L1 Flashcards
Replacement of adenine (A) with cytosine (C) in the codon GGA is an example of
Synonymous (silent) SNP
Explanation : Both GGA and GGC code for glycine.
Substitution of a nucleotide within a gene that does not result in a change in an amino acid in the expressed protein. Polymorphism type is ?
Synonymous (silent) SNP
nucleotide substitution in a gene that results in a change in the amino acid sequence of a protein. Polymorphism type is?
Non-synonymous SNP
guanine (G) is substituted for adenine (A) at nucleotide 46 in the β2-adrenergic receptor gene. This results in the substitution of glycine for arginine at amino acid position (codon) 16 and alterations in receptor down regulation on prolonged exposure to β2-receptor agonists. This is example of
Non-synonymous SNP
TPMT*3A polymorphism which the nucleotide guanine (G) is substituted for an adenine (A), resulting in an amino acid change from alanine (Ala) to threonine (Thr). Is an example of
Non-synonymous SNP
Abbreviation :
TPMT (Thiopurine methyl transferase )
Explanation:
The functional effect of theSTPMT*3A polymorphism includes both
1/ non-synonymous SNPs
2/results in decreased TPMT enzyme
activity.
3/ so lead to Increased risk of thiopurine toxicity (e.g., myelosuppression).
When nucleotide adenine (A) is substituted for a guanine (G), resulting in an amino acid change from tyrosine
(Tyr) to cysteine (Cys). This is example of
Non-synonymous SNP
what does Arg16Gly (or R16G) mean ?
glycine may be substituted for arginine at codon 16.
True or false?
( If a SNP changes the amount or function of a protein that contributes to drug response, it may alter kinetic properties or a patient’s sensitivity to a drug or predispose a patient to adverse reactions to drug therapy )
True ✅
A nucleotide change occurs, the resultant amino acid is no longer coded, and protein synthesis is terminated. What Polymorphism type is?
Premature stop codon polymorphisms .
CYP2C19*3 allele for which the nucleotide guanine (G) is substituted for an adenine (A). The change results in termination of protein synthesis. This is example of?
Premature stop codon polymorphisms
Note :
The proton pump inhibitors (PPIs) omeprazole and lansoprazole are drugs that are affected by the CYP2C19 genotype.
Explanation:
omeprazole area under the concentration time curve was 12- times higher in patients who had the CYP2C192/3 genotype compared with patients with the CYP2C191/1 genotype.
It occurs when there is an insertion of repeat nucleotides into the DNA sequence.The Polymorphism type is ?
Variable number tandem repeat polymorphism .
True of false ?
( In Variable number tandem repeat polymorphism The functional effect may be an increase, a decrease, or no effect on protein activity )
True ✅
The following example falls under any type of Polymorphism types ?
The Example is Uridine diphosphate glucuronyl transferase (UGT)
Variable number tandem repeat polymorphism.
Uridine diphosphate glucuronyl transferase (UGT)1A1 is an enzyme in which the UGT1A1*1 allele includes six dinucleotide repeats of thymine (T) and adenine (A) and results in normal enzyme activity. What The Polymorphism type is ?
Variable number tandem repeat polymorphism.
Explanation :
The UGT1A1*28 allele is an example of a tandem repeat polymorphism whereby an extra dinucleotide sequence of thymine (T) and an adenine (A) occurs.
This results in a total of seven dinucleotide repeats. The functional effect of the UGT1A1*28 allele is decreased UGT1A1 expression and enzyme activity.
True or false?
( The UGT1A128 allele is an example of a tandem repeat polymorphism whereby an extra dinucleotide sequence of thymine (T) and an adenine (A) occurs.
This results in a total of seven dinucleotide repeats. The functional effect of the UGT1A128 allele is decreased UGT1A1 expression and enzyme activity )
True ✅
