Baldness Gene

A condition of no hair or less hair or lack of hair in major areas on head is termed as baldness. It is also known by its scientific name androgenetic alopecia, which is often related to male pattern baldness. This anomalous condition is observed with a receding hair line at the top of head, leading to partial or complete baldness. However in women, this baldness does not cause a receding hairline but the thickness of the hair reduces with time and the hair becomes thinner and thinner in due course of time. The baldness in men is associated with various other medical afflictions that include coronary heart diseases and bladder and prostate glands enlargement. This condition has also been related to diabetes and obesity. In women, baldness is related to polycystic ovary syndrome (PCOS) which is a cause for hormonal imbalances leading to excess weight gain, irregular menstruation and hirsutism. The baldness cause has been attributed to the mutation of the androgen receptor gene (AR gene) which is also known as the baldness gene.

Baldness and Genetics
AR gene is primarily responsible for making the protein - androgen receptor. These receptors assist the body in responding positively to the androgen hormones that are responsible for sexual development and hair growth in a human. The androgen receptors bind with the androgen hormones in various tissues of the body and attach with the DNA to regulate the activity of androgen responsive genes. Every AR gene has a DNA segment - CAG which is a trinucleotide repeat. The number of CAG segment repeats can be less than 10 or in a range of 10-36. Characteristics like sex drive and hair growth are directly dependent on the proper functioning of these androgen responsive genes. Hence, any mutations in AR genes can lead to male pattern baldness. These variations can be a result of minor alterations in the DNA base pairs, that constitute the AR gene. Studies have shown that the hormone that is responsible for the mutation of AR gene is dihydrotestosterone (DHT), due to which the AR gene is also referred as the baldness gene. Due to this hormonal imbalance, the hair follicles show sensitivity to hair growth.

Hair growth is about an inch in every couple of months. The life span of a hair is 2-6 years from the time it shoots out of its follicle. Then when it falls out, a new hair starts growing from the follicle. Hence, 85% of the hair that grows on one's head is in growing phase. However, due to above stated genetic mutations in AR gene, there is a chance that the follicle starts shrinking with time, which leads to thinning hair and in due course of time, there is no hair that grows in the follicle. The follicle shrinking is often termed as follicle miniaturization. This is the reason for baldness in men. Also, the mutated AR gene is one of the causes for female pattern baldness. Recent studies have proved that the baldness gene is hereditary. Nowadays, there have been many male pattern baldness treatment options to defeat baldness in men. In females, baldness is not a common sign except in case of aging and post menopause contingencies. There have been cases where female pattern baldness has been attributed to the family history of male and female pattern baldness.

Therapy to Combat Baldness
With a lot of inventions and ongoing discoveries in science and genetics, generating new hair cells and strengthening the miniaturized hair follicles now seems a possible feat. Gene therapy now looks like one credible baldness cure. This therapy was first tried on mice. Patches of skin were removed from mice and were kept under observation during the course of experiments. It was observed that the cells not associated with hair follicles, due to some molecular changes in DNA, began to exhibit properties of genes found in their stem cells, thereby, leading to hair follicle formation. Hair growth was observed in this case, although, there was no pigment in the follicle. Researchers went a step ahead by experimenting on genetically engineered mice to produce higher levels of proteins for enhancing formation of follicle stem cells. In mice, twice the density of hair follicles were developed in comparison to the previous case. Now, this therapy is aimed at producing similar results in humans to combat the effects of this gene caused by mutated AR gene. This therapy is aimed at fixing DNA at molecular level, thereby generating DHT resistant hair follicles to facilitate more hair growth.

This gene was earlier believed to have been inherited from mother's side of family alone, as the male inherits the X chromosome from his mother. The X chromosome usually contains the androgen receptors. But off late, it has been proved that it can be passed on through father as well, as other genes are also involved in mutating the AR gene. Baldness in men is more evident than in women. However, there are baldness treatment methods for women also. Baldness gene, is still a research subject for identifying the precise cause for the baldness, although many gene therapies claim of regenerating hair.