Question

Match List-I with List-II
List-I (Characteristic):
(A). Restriction digestion followed by PCR amplification of selected fragments
(B). Use of PCR to amplify repeat motifs of DNA
(C). Variation in single nucleotides within a DNA sequence
(D). Detection of variations in the length of DNA fragments produced by restriction enzymes
List-II (DNA marker):
(I). RFLP
(II). SNP
(III). SSR
(IV). AFLP

• (A) - (II), (B) - (I), (C) - (IV), (D) - (III)
• (A) - (IV), (B) - (III), (C) - (II), (D) - (I)
• (A) - (IV), (B) - (III), (C) - (I), (D) - (II)
• (A) - (II), (B) - (I), (C) - (III), (D) - (IV)

Hint:

Remember:
- Single base change = SNP
- Repeat motifs = SSR (microsatellite)
- Hybridization + Restriction digest = RFLP
- Restriction digest + PCR amplification = AFLP

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Molecular markers are identifiable DNA sequences that can be used to track inheritance patterns, assess genetic diversity, and map genes.
These markers are categorized as hybridization-based, PCR-based, or sequencing-based based on the detection method used.

Step 2: Detailed Explanation:
Let us match each DNA marker type with its defining characteristic:
- (A) Restriction digestion followed by PCR amplification of selected fragments:
This describes AFLP (Amplified Fragment Length Polymorphism).
In AFLP, genomic DNA is digested with restriction enzymes, double-stranded adaptors are ligated to the ends, and a subset of the fragments is amplified using selective primers.
Thus, (A) matches with (IV).
- (B) Use of PCR to amplify repeat motifs of DNA:
This describes SSR (Simple Sequence Repeats, or microsatellites).
SSRs consist of tandemly repeated mono-, di-, tri-, or tetra-nucleotide motifs.
PCR primers designed from the flanking conserved regions amplify these highly variable repeat regions.
Thus, (B) matches with (III).
- (C) Variation in single nucleotides within a DNA sequence:
This describes SNP (Single Nucleotide Polymorphism).
SNPs represent a single base pair substitution (such as A to G) at a specific genomic location.
Thus, (C) matches with (II).
- (D) Detection of variations in the length of DNA fragments produced by restriction enzymes:
This describes RFLP (Restriction Fragment Length Polymorphism).
RFLPs are detected by digesting DNA with restriction enzymes followed by Southern hybridization with a labeled probe.
Polymorphisms arise from sequence variations that alter restriction site locations.
Thus, (D) matches with (I).
This pairing results in: (A) - (IV), (B) - (III), (C) - (II), (D) - (I), which matches Option (B).

Step 3: Final Answer:
The correct option is (B).