CPPS403 - IdentifyingDiseaseGenes I - 9 Flashcards
(15 cards)
What are the two types of genetic diseases based on mutation types and effect sizes?
Common diseases with noncoding variants and rare monogenic diseases with coding variants
Common diseases are often influenced by many small-effect variants, while monogenic diseases are typically driven by single large-effect mutations.
What are the approaches to identify disease genes?
- Linkage Analysis
- Association Analysis
- Genome Sequencing
These methods help in understanding the genetic basis of diseases by analyzing familial patterns or population data.
What is the purpose of linkage analysis?
To determine if a specific variant or genomic region is inherited in affected family members
This analysis helps in identifying regions of the genome that may contain disease-related genes.
What does association analysis investigate?
Whether certain genetic variants are overrepresented in affected vs unaffected populations
This method helps in finding genetic variants associated with diseases in different population groups.
What is genetic linkage?
The tendency for alleles at loci that are close together to be inherited together
This concept is fundamental in understanding how traits are passed down through generations.
What is a haplotype?
The set of alleles together on the same DNA segment that tend to be inherited together from the same parent
Haplotype analysis is crucial for localizing disease loci.
What is linkage disequilibrium (LD)?
A condition where certain markers are co-inherited
LD is important for identifying genetic variants associated with diseases.
How does recombination frequency relate to linkage?
Loci that are close together have low recombination frequency and are likely to be inherited together
High recombination frequency indicates independent assortment of alleles.
What is the significance of the HapMap project?
To characterize variations and create a map of haplotype blocks
It helps in understanding the genetic diversity and linkage disequilibrium across populations.
What is the goal of genome-wide association studies (GWAS)?
To identify common variants associated with diseases by genotyping high-density panels
GWAS typically involves thousands of cases and controls to find genetic associations.
What are Tag SNPs?
Particular combinations of alleles at nearby SNPs used to distinguish haplotypes
Tag SNPs simplify the genotyping process by representing blocks of genetic variation.
What is the process involved in whole-exome sequencing?
gDNA is sheared, enriched for exons using biotinylated baits, captured, sequenced, and interpreted
This method is useful for identifying mutations that cause rare monogenic disorders.
Fill in the blank: The closer loci are to each other, the ______ likelihood that they will be inherited together.
higher
This principle underlies the concept of genetic linkage.
True or False: Alleles at loci on different chromosomes assort independently.
True
This is a fundamental principle of genetics during meiosis.
What are the applications of next-generation sequencing (NGS) in Mendelian gene discovery?
- Sequencing across multiple unrelated affected individuals
- Sequencing multiple affected related individuals
- Sequencing parent-child trios for de novo mutations
NGS allows for the identification of novel variants that might be contributing to disease.
