A healthy couple, who paid little attention to family planning, gave birth to three children, all of whom had only one right hand. Why?

There is only one reason, that is, the couple's genetic factors.

A seemingly healthy couple, but because of temporarily unknown genetic reasons, all the children born are disabled.

Of course, some genetic diseases are passed from men to women, and some are passed from women to men. The men and women mentioned here refer to children.

I hope my answer can help you.