N.D.
L., Good question to ask. Most hydrocephalus can occur just by chance. However there are genetic conditions that have hydrocephalus including an x-linked type that only affects boys. I would suggest that your doctor refer you or your son for genetic counseling if you want to know if it is genetic in your family. If you or close relatives are planning more children they could give you more information about any risk or screening. If your doctor doesn't know a genetics center in the area you can search for one on the National Society of Genetic Counselors website http://www.nsgc.org/resourcelink.cfm
I hope that helps. All the best to you, N.