See what questions
a doctor would ask.
The Y chromosome is a sex-linked chromosome. Men are XY and women are XX, so only men have a Y chromosome. The Y chromosome is very small and contains few genes.
Y-linked transmission: The Y chromosome has a trivially simple inheritance pattern because women are XX and men are XY. Only men have a Y chromosome and so the Y is only passed from father to son. The Y chromosome is small and does not contain many genes. There are few genetic diseases related to genes on Y.
Male sex determination: The main Y gene is called the SRY gene, which is the master gene that specifies maleness and male features. It is the single gene that sets off the initial cascade of hormone changes that make a person male. It is not the entire Y chromosome, but just this gene that is necessary for maleness. There is evidence of this in rare diseases where the SRY gene is missing. People who are genetically male with XY chromosomes, but with a mutation or deletion of this SRY gene on the Y chromosome, will be female despite having most of the Y chromosome. And people who are genetically female with XX but also have a tiny piece of the Y chromosome with this gene, will become male despite their female-like XX chromosomes.
Search Specialists by State and City