The Y chromosome has long stood as a challenging puzzle in the vast landscape of human genetics. Its unique structure and role in determining male characteristics have intrigued scientists for decades. Now, with the Y chromosome sequenced fully, we are on the brink of a new era in genomic research. Understanding the full sequence can revolutionize our grasp on human development, diseases, and much more. Let’s explore why this milestone is a game-changer.
What is the Y chromosome?
The Y chromosome is a sex chromosome in humans. It is the third smallest human chromosome.
Along with the X chromosome, it represents one of the 23 pairs of human chromosomes in each cell.
Every person usually has one pair of sex chromosomes in each cell.
Males have both the X and Y chromosomes, while females have a pair of X chromosomes.
The Y chromosome likely contains almost 200 genes that provide instructions for protein formation.
Since it is only found in males, the Y chromosome is vital in male sex determination and development.
The SRY gene in the Y chromosome is responsible for developing a fetus into a male.
Recent studies have shown that genes on the Y chromosome are associated with developing certain diseases.
Changes in the Y chromosome have been associated with the development of certain cancers in men.
Role Of The Y Chromosome In
Genetic Diseases
Mosaic loss of the Y chromosome is a biomarker for developing certain diseases.
Studies have found that this loss is associated with the severity of diseases.
Loss of Y chromosomes in bone marrow is associated with abnormal growths or myeloid neoplasia.
Decreased expression of Y-linked genes was found in older patients who have Alzheimer’s disease.
Loss of the Y chromosome is also associated with rare autoimmune diseases like autoimmune thyroiditis and primary biliary cirrhosis.
Infertility
Y chromosome infertility is a condition where sperm production is impaired.
An affected man may produce fewer than normal sperms, sperms that are abnormally shaped or don’t show proper movement.
This condition makes it difficult or impossible for a man to father children.
Mutations in the Y chromosome are usually the cause of this condition.
Certain areas of the Y chromosome called azoospermia factor (AZF) regions code for the proteins involved in sperm production.
Deletion of genes in this region affects sperm production and causes Y chromosome infertility.
This condition is usually not inherited and does not run in families.
It occurs due to new deletions in the Y chromosome of the affected individual.
Cancer Risk And Severity
Reduced chances of survival for Barret’s adenocarcinoma were reported with complete or partial loss of the Y chromosome.
Loss of the Y chromosome in bladder cancer cells helped tumors evade the immune system.
Loss of the Y chromosome is 77% more commonly found in renal cell carcinoma.
Sequencing The Y Chromosome: What Scientists Have Found
The human Y chromosome was the only one yet to be fully sequenced.
A team of researchers funded by the National Human Genome Research Institute has finally fully sequenced the human Y chromosome.
The Y chromosome’s genome has so far remained a mystery.
Unlike other chromosomes, the Y chromosome has a significantly high repetitive sequence.
Almost half of the chromosome comprises two alternative sequences known as satellite DNA.
Researchers have also closely studied the azoospermia region, a stretch of DNA on the chromosome that regulates sperm production.
The study also showed that humans can have between 10 to 40 copies of the TSPY gene on the Y chromosome.
The TSPY gene is involved in some production.
These findings pave the way for the future of genomic medicine.
Pangenome Y And Future Directions
Sequencing the Y chromosome has opened doors for many future discoveries.
Pangenome is a new term for genomics that combines genetic data received from people of different backgrounds and uses it to diagnose diseases and guide treatment options.
Researchers plan to now include complete sequences of the Y chromosome into individual genomes that comprise the pangenome.
It will help us understand how the Y chromosome varies in people from different parts of the world.
Conclusion
The Y chromosome is one of the smallest human chromosomes.
It is associated with sex determination in men.
However, the changes in the Y chromosomes are now associated with the development and severity of many diseases.
It is associated with Alzheimer’s disease and many cancers.
Mutations in the Y chromosome can also cause infertility in men.
Scientists have now fully sequenced the Y chromosome.
It will pave the way for better diagnosing and treating many common Y-linked diseases.
Reference
https://medlineplus.gov/genetics/condition/y-chromosome-infertility/
https://www.nih.gov/news-events/nih-research-matters/y-chromosome-affects-cancer-growth#
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4908225/
