From the Guidelines
The primary gene for baldness is inherited from the mother, as it is located on the X chromosome, which men inherit only from their mothers. This is supported by the fact that androgenetic alopecia (AGA) is influenced by the androgen receptor gene on the X chromosome, as mentioned in a 2025 study published in Periodontology 2000 1. According to this study, AGA affects 58% of men by age 50, and its pattern is highly reproducible, suggesting a strong genetic component.
Key Points to Consider
- Baldness is not determined by a single gene, but is polygenic, meaning multiple genes are involved, including some from the father's side 1.
- The androgen receptor gene on the X chromosome affects how sensitive hair follicles are to dihydrotestosterone (DHT), a hormone that can cause follicles to shrink and eventually stop producing hair.
- While looking at the maternal grandfather's hair pattern can provide some insight into a man's potential for baldness, it's not a perfect predictor because other genetic and environmental factors also play important roles 1.
- Women can experience hair thinning too, but typically in a different pattern than men, with central region thinning and a preserved frontal hairline, as described in the study 1.
Implications for Morbidity, Mortality, and Quality of Life
- Hair loss can result in detrimental psychological effects and impact an individual's quality of life, as noted in the study 1.
- Understanding the genetic basis of baldness can help individuals take preventive measures and seek treatment to improve their quality of life.
From the Research
Genetic Factors in Baldness
- The question of whether bald genes come from women is complex and multifaceted, involving various genetic and hormonal factors 2.
- Androgenetic alopecia (AGA), also known as male or female pattern hair loss, is influenced by a combination of genetic, hormonal, and environmental factors 3, 4.
- While there is no direct evidence to suggest that bald genes exclusively come from women, research indicates that AGA can be inherited from either parent, with certain genetic variants contributing to the condition 2.
Inheritance Patterns
- The inheritance pattern of AGA is not strictly maternal or paternal, but rather a complex interplay of multiple genetic and hormonal factors 2, 4.
- Studies have shown that individuals with a family history of AGA are more likely to develop the condition, regardless of the affected parent's sex 2, 5.
- However, the specific genetic mechanisms underlying AGA and its inheritance patterns require further research to fully understand 3, 6.
Treatment Options
- Various treatment options are available for AGA, including topical minoxidil, oral finasteride, and low-level laser therapy, among others 3, 4, 5, 6.
- The effectiveness of these treatments can vary depending on individual factors, such as the severity of hair loss and the presence of underlying medical conditions 4, 5.
- A comprehensive approach to treating AGA may involve a combination of medical therapies, lifestyle modifications, and, in some cases, hair transplantation 6.