Males, on the other hand, who have nothing to fall back on, are forced to fully express their faulty genes.
Because males have only a single X chromosome, more genetic diseases have been found on this chromosome than any other,
said Dr Ian Jackson of the MRC Human Genetics Unit, UK. One consequence is that boys have a higher incidence of mental retardation than girls.
The high quality DNA sequence published here has already aided the identification of numerous disease genes. There are many more to be discovered and this sequence will be invaluable for tracking these genes down.
