testesterone

I would like to know all there is to know about testosterone. My brother was diagnosed with testosterone deficiency. Can someone tell me if this is something serious? Will he be ok? What are the signs and symptoms of this condition?

Testosterone is the androgenic hormone. It is primarily responsible for normal growth and development of male sex and reproductive organs, like the penis, testicles, scrotum, prostate, and seminal vesicles. Testosterone production declines naturally with age and the testosterone deficiency may result from disease or damage to the hypothalamus, pituitary gland. This can also be cause by testicles that inhibits hormone secretion and testosterone production, and is also known as hypogonadism. Depending on age, insufficient testosterone production can lead to abnormalities in muscle and bone development, underdeveloped genitalia and diminished virility. Signs and symptoms of this condition depend on the age of onset and the duration of hormonal deficiency. Congenital testosterone deficiency is generally characterized by underdeveloped genitalia and adult men may experience diminished libido, erectile dysfunction, muscle weakness, depression, and other mood disorders. I truly hope that your brother will be ok.

Just wondering how old your brother is , and if he ever did a chromosone test. Some men do have an extra x chromosone, 47 xxy, or sometimes more than one extra ,48 xxxy ( Kleinfelters syndrome), and not know it.
Don't know if that could be a possibility, since I am not a medical professional.