Thalassemia occurs due to which mutations
A. MissenseB. Splicing
C. Transition
D. Frame-shift
E. Truncation
Ans. B) Splicing; D) Frame-shift
Important causes of
thalassemia are
• β—thalasssemia : A wide variety of mutations in β—globin gene
including deletion, nonsense and Frameshift mutation, and
others affecting every aspects of its structure (e.g. splicing sites, promotor
mutans)
•α-thalassemias . Mutations in α-globin gene mainly unequal crossing over and large DELETIONS and less commonly nonsense and Frame shift mutations.
•α-thalassemias . Mutations in α-globin gene mainly unequal crossing over and large DELETIONS and less commonly nonsense and Frame shift mutations.
•
Mutations causing β-thalassernia can affect at any step in the pathway of globin
geneexpression transcription, processing of m-RNA precursors, translation and
post translational meta bolism of β—gIobin polypeptide chain
•
The most common forms arise from mutations that derange SPLICING of mRNA
precursor or permenantly terminate translation of mRNA.
