Helping people with sex chromosome aneuploidies (SCAs)
live healthier lives.
Patients, families, doctors, and researchers working together to learn more.
Understanding Why You Belong Here
What are Sex Chromosome Aneuploidies (SCAs)
Sex chromosome aneuploidies (SCAs) are genetic conditions. They happen when a person is born with an extra or missing X or Y chromosome.
Most people have two sex chromosomes, like XX or XY. People with SCAs may have a different number, like XXY or XYY or just one X. Often people refer to these as their genetic signature.
Each person with an SCA is unique, even when they share the same genetic signature. Some people may have few symptoms, while others may need more medical care or support.
What are Sex Chromosome Aneuploidies (SCAs)
Sex chromosome aneuploidies (SCAs) are genetic conditions. They happen when a person is born with an extra or missing X or Y chromosome.
Most people have two sex chromosomes, like XX or XY. People with SCAs may have a different number, like XXY or XYY or just one X. Often people refer to these as their genetic signature.
Each person with an SCA is unique, even when they share the same genetic signature. Some people may have few symptoms, while others may need more medical care or support.
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Participants make it possible for researchers to find new treatments, speed diagnosis and improve the lives of those affected by rare diseases.
Join One of Our Research Studies
Participants make it possible for researchers to find new treatments, speed diagnosis, and improve the lives of those affected by rare diseases.
Rare Research Report: April 2026
Each month, we share summaries of recent Rare Diseases Clinical Research Network (RDCRN) grant-funded publications.
