Men who start to go bald even before a mid-life crisis may have their mothers to blame, according to a new study. Researchers have found that the main construction manual for a full head of hair is located on the X chromosome, which sons always inherit from their mothers. However there are skeptics who deny this co-relation.
This genetic storage space contains the so-called androgen receptor gene, a long time balding suspect. Looking at men who were losing their hair at a relatively young age, a team led by Markus Nothen, PhD, of the Life & Brain Center at Bonn University, Germany systematically examined all of the genetic patterns within the X chromosome to see why certain hairlines recede faster than others. It’s not a pretty picture.
The study, published in the American Journal of Human Genetics, claims that a single alteration in the androgen-receptor gene is the major reason why some men end up going bald before their fathers. Nearly half of bald men would not be bald if they did not have this genetic variation. The hair loss in these younger men, he added, was much more severe than in the men who still had a reason to use a comb in their 60s.
The two approved medicines to treat hair loss (Rogaine and Propecia) need to be taken for a long time to see results. With Propecia, doctors sometimes advise their patients not to expect any results before at least six to eight months. And both need to be used indefinitely to maintain its effect. Once you stop, hair loss will continue.
Hair Loss Heredity Connection
Although there are only two medicines approved by the Food and Drug Administration (FDA) to treat hair loss, many people are interested in other, alternative treatments. The herb saw palmetto has been used for many years in Europe to treat symptoms of an enlarged prostate and there is some evidence that it may also be effective in treating hair loss.
Hair color is determined by the amount of a pigment called melanin in hair. An abundance of one type of melanin, called eumelanin, gives people black or brown hair. An abundance of another pigment, called pheomelanin, gives people red hair.
|The type and amount of melanin determines hair color|
|Hair color||Type and amount of melanin|
|Black||Large amount of eumelanin|
|Brown||Moderate amount of eumelanin|
|Blond||Very little eumelanin|
|Red||Mostly pheomelanin with a little eumelanin|
The type and amount of melanin in hair is determined by many genes, although little is known about most of them. The best-studied hair-color gene in humans is called MC1R. This gene provides instructions for making a protein called the melanocortin 1 receptor, which is involved in the pathway that produces melanin. The melanocortin 1 receptor controls which type of melanin is produced by melanocytes. When the receptor is turned on (activated), it triggers a series of chemical reactions inside melanocytes that stimulate these cells to make eumelanin. If the receptor is not activated or is blocked, melanocytes make pheomelanin instead of eumelanin. Many other genes also help to regulate this process. Most people have two functioning copies of the MC1R gene, one inherited from each parent. These individuals have black or brown hair, because of the high amount of eumelanin. It is estimated that more than 90 percent of people in the world have brown or black hair.
Variation in Genes and Hair Color
Some people have variations in one copy of the MC1R gene in each cell that causes the gene to be turned off (deactivated). This type of genetic change is described as loss-of-function. For these individuals, eumelanin production is lower, while pheomelanin production is higher, so they have strawberry blond, auburn, or red hair. In an even smaller percentage of people, both copies of the MC1R gene in each cell have loss-of-function changes, and the melanin-production pathway produces only the pheomelanin pigment. The hair of these individuals is almost always very red. Even when the melanin-production pathway is making eumelanin, changes in other genes can reduce the amount of eumelanin produced. These changes lead to blond hair.
Hair color ranges across a wide spectrum of hues, from flaxen blond to coal black. Many genes other than MC1R play a role in determining shades of hair color by controlling levels of eumelanin and pheomelanin. Some of these genes, including ASIP, DTNBP1, GPR143, HPS3, KITLG, MLPH, MYO5A, MYO7A, OCA2, SLC45A2, SLC24A5, TYRP1, TYR, ERCC6, GNAS, HERC2, IRF4, OBSCN, SLC24A4, TPCN2, and MITF, are involved in the production of melanin in hair. Some of these genes are associated with gene transcription (which is the first step in protein production), DNA repair, the transport of substances (such as calcium) across cell membranes, or the structure of hair follicles. Several of these genes contribute to eye and skin color, but the exact role they play in determining hair color is unknown.
Hair color may change over time. Particularly in people of European descent, light hair color may darken as individuals grow older. For example, blond-haired children often have darker hair by the time they are teenagers. Researchers speculate that certain hair-pigment proteins are activated as children grow older, perhaps in response to hormonal changes that occur near puberty. Almost everyone’s hair will begin to turn gray as they age, although when it happens and to what extent is variable. Gray hair is partly hereditary and may vary by ethnic origin; it is also somewhat dependent on external factors such as stress. Hair becomes gray when the hair follicle loses its ability to make melanin, but exactly why that occurs is not clear.