Correct option is D
Explanation-
Statement A: "AFLP markers can discriminate between homozygote and heterozygote genotypes." - INCORRECT
AFLP (Amplified Fragment Length Polymorphism) markers are dominant markers, meaning they can only indicate presence or absence of a specific fragment, but cannot differentiate between homozygous dominant (AA) and heterozygous (Aa) genotypes. They simply give a band or no band result, making it impossible to know the zygosity status.
Statement B: "Microsatellites (eg., SSR) are capable of detecting higher level of polymorphism than RFLP." - CORRECT
Microsatellites (Simple Sequence Repeats - SSRs) consist of short tandem repeats (e.g., CA repeats). They are highly polymorphic due to frequent variations in repeat number between individuals. Compared to RFLP (Restriction Fragment Length Polymorphism), SSRs offer more allelic diversity, higher resolution, and are more informative in population genetics.
Statement C: "SNPs are more prevalent in the coding regions of the genome." - INCORRECT
Single Nucleotide Polymorphisms (SNPs) are found throughout the genome, but they are more frequent in non-coding regions like introns and intergenic spaces.
Coding regions are under selective pressure, so fewer SNPs occur there because changes can be harmful.
Statement D: "SNP markers are the most suitable markers for both foreground and background selection." - CORRECT
SNPs are co-dominant markers and are very abundant and uniformly distributed across the genome. Because of their high density and genome-wide coverage, they are ideal for - Foreground selection (tracking a target gene or QTL)
and Background selection (recovering the recurrent parent's genome during breeding). Also, SNP genotyping is high-throughput, cost-effective, and widely used in marker-assisted selection.
Final Correct Combination:
B and D only (Option d)
