▶ Previous Artlcle: #2-6. Basic Knowledge of Hair Loss 

 

 

Hereditary Factors

 

Androgenetic alopecia, also known as male-pattern hair loss, occurs only when there exist baldness genes.

 

Even after puberty and male hormones are produced in abundance, hair loss does not occur in people who have no genetic predisposition.

 

 

HELIOSⅡ/LOTUSⅡ/HYPERION – Manufacturer: LASEROPTEK(www.laseroptek.com)

 

 

Chromosomes always exist in pairs.

 

Humans have 23 pairs of chromosomes and each parent contributes one chromosome to each pair – a pair of sex chromosomes (XX or XY) and 22 pairs of autosomal chromosomes.

 

A widely accepted opinion is that androgenetic alopecia is considered to be inherited in an autosomal dominant manner.

 

Baldness genes can be inherited from either paternal or maternal lines, but are more affected by mother’s side of the family.

 

However, simply having the baldness genes does not necessarily mean going bald.

 

 

Figure 1. Autosomal Dominant Inheritance. 

 

 

The expression of a particular gene by individuals who have a certain phenotype refers to expressivity. 

 

In fact, expressivity that causes alopecia is closely related with such factors as hormones, ages, and stress.

 

There are many people not going through hair loss while their grandfather and father develop alopecia, because they do not inherit baldness genes or have baldness genes that lacks expressivity.

 

 

 

-To be continued