2026 Year-End Campaign

Every Child Deserves More Than a Diagnosis.

Every child deserves the chance to flourish. Your gift helps IDefine move Kleefstra syndrome research from research ready to treatment focused — turning questions into answers, answers into treatments, and hope into possibility.

Help us raise $150,000 by January 5 to accelerate the research families are waiting for.




Driving progress toward treatments and a cure for Kleefstra syndrome


Latest Research & Community Updates

CSO Corner, Volume 17: Turning Up the Volume on EHMT1, Part 2
Hello fellow members of our KS family! As you probably know, at its core, Kleefstra syndrome (KS) is caused by damage to one copy of the gene EHMT1. Since...

IDefine is a nonprofit organization dedicated to supporting individuals and families affected by Kleefstra syndrome while accelerating research toward new treatments and eventually a cure.

Through IDefine, families can connect, share experiences and access trusted information so they do not need to navigate KS alone.

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