Your browser is too old
We can't provide a great video experience on old browserUpdate now
This sqadia.com medical video lecture solely explains the examples of genetic mutations. Maham Afridi begins by explaining complex genetics of cystic fibrosis, variations in one gene one protein hypothesis, and mutation in DNA sequence such as beta thalassemia. After that tandem repeats, dyskeratosis congenita, in conjunction with transposable elements are described. Mutations in RNA are also elaborated.
Gene Protein Relationship
At first, timeline of gene protein relationship is presented. After that genotype-phenotype correlation is highlighted with the help of diagram. Then educator explains the complex genetics by taking cystic fibrosis as an example. Cystic fibrosis is a physiological cascade of abnormal Cl- transport. Maham Afridi also notifies about variations in one gene one protein hypothesis.
Mutation in DNA Sequence
Mutations in DNA sequence results in missing protein product while changes in coding sequence produces a structurally abnormal product. Degenerative nature of DNA code is elaborated by wobble in protein translation and silent changes. Then beta thalassemia is discussed which is a disorder of Hb molecule. Role of pseudogenes in medicine is also described.
Tandem repeats are clustered repeated nucleotides i.e. next to each other and oriented in the same direction. Tandem repeats are further classified into satellites, minisatellites and microsatellites. All of these are discussed in succession by Maham Afridi. Following this, a multisystem disorder dyskeratosis congenita (DC) is illuminated which is of 2 forms i.e. one form is X-linked and the other is autosomal dominant.
This section is the elaboration of trinucleotide repeat disorders which is a group of neurogenetic disorders that share a common pathophysiology. Features of lynch syndrome also known as hereditary non-polyposis colorectal cancer (HNPCC) are also considered. Moving onward, educator talks about conditions associated with higher mutation rate.
Mutations in RNA
Clinical conditions associated with mutations in tRNA include Charcot-Marie-tooth disease, peripheral neuropathies, Alzheimer disease. Changes in rRNA leads to defects in ribosome biogenesis and problems with RBCs production. Abnormalities in miRNA are implicated in cancer, cardiac problems and neurologic changes. Significant cognitive deficits along with various other conditions is reported extensively.