In News: Researchers at the Indian Institute of Technology (IIT), Madras, Tel Aviv University and Columbia University are studying a rare genetic brain disease called “GNB1 Encephalopathy” and trying to develop a drug to treat it effectively.
GNB1 Encephalopathy
It is a kind of brain disease or neurological disorder which affects individuals in the foetus stage.
With less than 100 documented cases worldwide
Children born with GNB1 mutation experience delayed physical and mental development, intellectual disabilities, epilepsy (abnormal brain activity), movement problems, muscle hypotonia or hypertonia.
A potassium channel called G-protein gated Inwardly Rectifying K+ (GIRK) channel (present in brain, heart and endocrine glands) function is affected significantly.
As I80T mutation is the most prevalent variant in GNB1 encephalopathy patients.
How it occurs:
A single nucleotide mutation in the GNB1 gene that makes one of the G-proteins, the “Gβ1 protein,” causes Encephalopathy.
Every cell in the human body has a wide variety of signalling molecules and pathways that help in communicating with other cellsand within itself.
The major signalling mechanism used by cells is ‘G-Protein Coupled Receptor’ (GPCR) signalling.
GPCR is a receptor that receives a signal (e.g. a hormone, light, neurotransmitter) from the outside of the cell and transduces it to the inside of the cell.
GPCR is present in the cell membrane and has a G-protein (αβγ) attached to it from inside the cell.
G-proteins are the immediate downstream molecules that relay the signal received by the GPCR.
These G-proteins are present in every cell, and any malfunction will cause disease.
Treatment:
As the developmental issues start at the fetal stage, gene therapy is the most plausible option to alleviate the effects of the mutation.
Whole genome sequencing, the elucidation of the full genetic analysis of the baby, can be very helpful in early diagnosis of the disease.
Epilepsy can be treated using specific drugs to increase the patient’s quality of life.
To treat epilepsy, specific targets have to be identified.
Most epilepsies are caused due to alteredion channel function.
Ion channels are proteins that underlie the electrical activity of neurons and heart cells.
Q.1) In the context of hereditary diseases, consider the following statements: (2021)
Passing on mitochondrial diseases from parent to child can be prevented by mitochondrial replacement therapy either before or after in vitro fertilization of egg.
A child inherits mitochondrial diseases entirely from mother and not from father.
Which of the statements given above is/are correct?
