Due to an autosomal recessive gene. Caused by a mutant gene on the X chromosome. Pale skin, white hair and eyes lacking pigment, due to mutation of genes involved in the production of melanin. Vision is often impaired. This gene governs production of the male hormone responsible for timely development of the penis and scrotum in XY embryos.
Affected children appear to be females at birth, but they become masculinized at puberty.
At that time, the penis enlarges, the testicles may descend into the labioscrotal sac, the voice deepens and the male muscle mass appears. Due to mutation of an autosomal gene involved in the production of the male hormone, testosterone. Progressive loss of hearing and chronic kidney disease. Generally the condition appears in later life but early onset varieties are known. Due to an autosomal dominant gene, possibly on chromosome 21.