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• a  concerning characteristics that are determined by genes carried on the sex chromosomes (on the X chromosome in particular)

• But the procedure was designed to help parents who carry genes for "sex-linked" diseases, such as hemophilia and Duchenne muscular dystrophy, that occur almost exclusively in boys.
• When their doctor shares their curiosity, though, he may well fear the presence of some sex-linked hereditary disease such as hemophilia, or certain disorders accompanied by mental .
• IVF recruited couples who wanted a child of a particular sex, either to bring "gender balance" to their family or to help them avoid sex-linked genetic diseases for which their .