SizeGenetics Penis Extender This is the most powerful device on the internet...  SizeGenetics has received the most press and airtime, it has been proven by users to be the best. Voted best penis enlargement product of 2004-2005. Read product review on SizeGenetics  |  Order SizeGenetics

How Human Genetics Determine Penis Size?

The size of the penis is decided for men while they are still embryos floating in the confines of the female uterus. One may say that the size of the penis can actually determined even before conception by forecasting the effects of the combination of genetic material from the two parents. However, there is no known reliable method for such forecasting.

At the physical level, the penis size is handled by the HOX genes. This family of transcription factors play a key role in body patterning during the embryonic stage of development. Humans have 39 HOX genes organized in four clusters and tasked with major roles in the development of the nervous system, axial skeleton, external genitalia and limbs. This situation could one day provide the definitive proof of the existence or lack of connections between the size of the limbs and that of the penis. Many people believe that the size of the penis can be estimated from the size of hands or feet and the fact that the same genes handle the formation of both genitalia and limbs could provide the missing clues.

Mutations in these genes could trigger malformations to the external genitalia, such as the micropenis (when the penis is less than half an inch in size) or the macropenis, which is a penis of abnormally large size.

The size of the penis can also be influenced by the level of exposure to various hormones of the developing embryo. One study based on data provided by professor Alfred Kinsey found that homosexual men have statistically larger penises than heterosexuals, which could be explained by exposure to estrogen.