Imagine a genetic disorder which is caused by one of the point mutations describ
ID: 89330 • Letter: I
Question
Imagine a genetic disorder which is caused by one of the point mutations described in this week’s lecture. Walk through the entire processes of transcription and translation and explain how the mutation might interact with each step. Be thorough in your descriptions. Imagine a genetic disorder which is caused by one of the point mutations described in this week’s lecture. Walk through the entire processes of transcription and translation and explain how the mutation might interact with each step. Be thorough in your descriptions.Explanation / Answer
point mutation is a genetic disorder in which one nucleotide is susbtituted with another bringing change in the protein.
now i dont what types of point mutations are taught in your classes, but i l try to give the general view how point mutation will affect the normal function by taking sickle cell anemia. so dont get me wrong.
let us assume that the sequence of astructural gene has the following sequence
------------------AAA-------------
------------------TTT-------------- normal gene
l transcription occurs
l
---------AAA----------------- mRNA
l
---------LYS-------------- so this protein will have a normal function
consider if a point mutation has occured
--------------AAA-----------
--------------TTA----------
l trnascription occurs
---------------AAU----------
I translation occurs.
----------------ASN----------
for further understanding, take the example of sickle cell anemia. in this beta globin chain of hemoglobin hydrophillic glutamic acid is replaced with hydrophobic valine at 6th position. due to which HbS is formed.
AUG GUG CAC CUG ACU CCU GAG GAG AAG UCU GCC GUU ACU normal gene
start Val His Leu Thr Pro Glu Glu Lys Ser Ala Val Thr
point mutation leads to
AUG GUG CAC CUG ACU CCU GUG GAG AAG UCU GCC GUU ACU
START Val His Leu Thr Pro Val Glu Lys Ser Ala Val Thr