Is it possible for a human male to be a carrier?

Question

of a sex-linked trait?

Answer 1

Yes a male can be a carrier of a sex chromosome linked genetic trait. Humans have 233 chromosomes in every cell of our bodies, (except red blood cells where they degenerate.). The 22 autosomal (= non-sex) cheomosomes come in a pair one derived form the set in the egg and the other from the sperm cell. Human sex chomosomes are different. In a female there is a pair of substantially identical sex chromosomes called the "x" chromosome. Males have one x chromosome and a much smaller y chromosome. The y chromosome is missing a lot of the genes located on the full sized x chromosome. So if one of those missing genes (not on the y cheomosome), is defective. The male espresses the defective gene. The expression will happen even if the trait (gene) is not dominent, called recessive. A non dominent gene's trait will usually not show up if the person has only one defective gene but the other crresponding gene is not defective. If that person is male there is no other corresponding gene to correct the problem. Exmples of such sex limked traits are male color blindness, hemophelia (types 6 and 7), and some types of pattern baldness.
The male will pass the sex-linked deective gene (originally derived from his mother), to his daughters. That gene is not on his y chromosome. Each daughter will get his x gene and most probably a normal x gene from her mate. The daughters become carriers and their children may expressed the disease/ Their boys have a 50/50 chance of acquiring the defective x chromosome and its defective gene. (boys sex chromosomes are xy). Women must have two x-linked defective recessive sex linked chromosomes to express the defective gene.
Dan.

Answer 2

In a simple word, yes.

For sexually-related items, this means the "dominant" trait would be carried on (or strongly associated with) the Y-chromosome.

If the offspring was a boy, the trait would (probably) assert itself, but not necessarily. If the offspring were a girl, it's probable that the trait would not be present.

The above example was based on something solely linked to the Y chromosome (meaning it had to be present). If, for some reason, the Y-chromosome carried a trait inhibitor, then the reverse would be true ... it would tend to show up in girls, not boys.