a.
To hypothesize:
The mechanism by which each of the three SCN9A mutations affects gene structure and the reason due to which truncated proteins are made in each case.
Introduction:
The SCN9A gene has 26 exons and encodes a 1977-amino acid polypeptide. The homozygosity for extremely rare mutations in the SCN9A gene cause complete insensitivity to pain called congenital pain insensitivity or CPA, and a total lack of the sense of smell called anosmia.
b.
To determine:
Whether the mutant alleles cause loss of function or gain of function and whether they are amorphs, hypomorphs, hypermorphs, neomorphs, or antimorphs.
Introduction:
The information in DNA is the starting point of gene expression. The cell transcribes that information into mRNA and then translates the mRNA information into protein. Mutations can alter the
c.
To explain:
The mechanism due to which CPA or anosmia is a recessive condition in molecular terms.
Introduction:
Mutations affect
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ND STONY BROOK UNIVERSITY LOOSELEAF GENETICS: FROM GENES TO GENOMES
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- Biology Today and Tomorrow without Physiology (Mi...BiologyISBN:9781305117396Author:Cecie Starr, Christine Evers, Lisa StarrPublisher:Cengage Learning