Question

1. Point out one example of an indel and one example of SNP. Write down the significance of these two polymorphisms.

Answer 1

An insertion/deletion polymorphism commonly abbreviated indel is a type of genetic variation in which a specific nucleotide sequence is present (insertion) or absent (deletion). While not as common as SNPs, indels are widely spread across the genome.
example - common microindel which results in a frameshift causes Bloom syndrome in the Jewish or Japanese population. indels can be contrasted with a point mutation. Indela are likely to represent between 16% and 25% of all sequence polymorphism in humans.

SNP polymorphism is a DNA sequence variation occurring when a single nucleotide adenine (A), thymine (T), cytosine (C), or guanine (G]) in the genome (or other shared sequence) differs between members of a species or paired chromosomes in an individual.
Example - The substitution of a C for a G in the nucleotide sequence AACGAT, thereby producing the sequence AACCAT. The DNA of humans may contain many SNPs, since these variations occur at a rate of one in every 100-300 nucleotides in the human genome.

Significance of polymorphism :-

The phenomenon of polymorphism is essentially one of division of labour in which specific functions are assigned to different individuals. Thus, polyps are modified for feeding, protection and asexual reproduction, while medusae are concerned with sexual reproduction.