Building Our Community - Support Today!

This week, families, researchers, and clinicians are together in Waltham, Massachusetts for our 2026 Kleefstra Syndrome Family Conference + Scientific Summit — a powerful reminder of how far this community has come, and how much closer we are to real treatments.

IDefine is the leading nonprofit patient advocacy organization dedicated to advancing research, building community, and driving progress toward new treatments — and eventually a cure — for Kleefstra syndrome (KS). Founded in 2020 by parents of children diagnosed with KS, we bring urgency, determination, and a deeply personal commitment to changing outcomes for every family living with this condition.

Advancing Research, Together

In just a few years, IDefine has helped build the scientific and clinical foundation needed to pursue real treatments — funding and helping establish the first dedicated Kleefstra Syndrome Center of Excellence at Boston Children's Hospital, supporting natural history studies, and developing patient-derived research models used by scientists around the world. Today, that foundation is powering the next generation of research, including strategic collaborations with Unravel Biosciences, UT Southwestern, and the University of Chicago exploring gene therapy and other promising paths to treatment. With continued investment, we believe meaningful treatments could be possible within the next five years.

Building a Connected Community

None of this is possible without community. Through conferences, connection, and shared knowledge, IDefine ensures no family faces Kleefstra syndrome alone — bringing patients, caregivers, clinicians, and researchers together to support one another and drive progress side by side.

Your gift today helps accelerate research, strengthen clinical care, and keep our community connected. Kleefstra syndrome is at a pivotal moment, and with your support, we can move faster toward the treatments our families have been waiting for.

What is Kleefstra Syndrome?

Kleefstra syndrome (KS) is a rare genetic neurodevelopmental disorder caused by a variant or deletion of the EHMT1 gene, which plays a critical role in brain development. KS can cause a wide range of features, including intellectual disability, speech delay, low muscle tone, seizures, and behavioral challenges, with severity ranging from mild to profound. KS is estimated to affect about 1 in 30,000 births — roughly 10,000 people in the U.S. and 250,000 worldwide.

IDefine, Inc. is a Georgia nonprofit corporation and a tax-exempt public charity under Section 501(c)(3) of the Internal Revenue Code (Federal Tax ID/EIN: 85-1404717). Contributions to IDefine are tax-deductible to the fullest extent of the law.