Skip to content
Login Register

#STR

2 public questions tagged with this topic.

Molecular Marker

Which polymorphism is caused by replication slippage?

Mechanism of polymorphism generation differs among markers. Short Tandem Repeats arise from DNA polymerase slippage during replication where nascent strand misaligns on template in repetitive tract, adding or deleting few repeat units. This slippage model explains high mutation rate of microsatellites and multiallelic length variation. RFLP results from point mutation affecting restriction site, SNP from single nucleotide substitution, ISSR from amplification between microsatellite loci. Replication slippage specifically underlies STR variation, supporting use in population genetics where high variability is advantageous.

Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.

View Details
Molecular Marker

Which DNA-based marker is best for high-throughput genotyping?

High-throughput genotyping demands markers that are extremely abundant, evenly distributed across chromosomes, biallelic, easily automated and suitable for multiplexed detection in parallel reactions. Single Nucleotide Polymorphisms fulfill these requirements with occurrence every few hundred bases, amenable to array-based chips, next-generation sequencing and fluorescence-based assays producing millions of genotypes rapidly with minimal DNA input. SSR, VNTR and RAPD rely on gel electrophoresis and manual allele sizing, limiting throughput and automation. SNP platforms offer cost-effective scalable screening for association studies and genomic selection programs.

Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.

View Details