The knee maven found
this in today's NY Times: a few studies looking at familial and genetic issues that may identify folks more at risk for acute ACL injury during athletic training. Not that genetic screening before doing m.a. or sports is on the horizon, but if you have close family members who have had acute ACL injuried you may want yourself and/or your children to be aware of higher potential risk and perhaps focus more on things that may help prevent such injuries (working w/ coach or traininer to learn proper body mechanics and plyometrics, building hamstring strength, etc).