ABOUT TRISOMY 9
What is Trisomy 9?
Our bodies are made up of cells, and inside most cells are chromosomes, which carry our genes. Genes act like instructions that help guide growth and development. Most people have 46 chromosomes, arranged in 23 pairs.
Trisomy 9 is a rare chromosome condition in which there is extra genetic material from chromosome 9. This can happen in different ways. Some children have extra chromosome material in only some of their cells (called mosaic Trisomy 9), while others have an extra copy of part or all of chromosome 9. Because of this, Trisomy 9 can look very different from one child to another.
Children with Trisomy 9 may experience medical, developmental, or learning differences, but the range of outcomes is wide. Many factors—including how much extra chromosome material is present and where it occurs—can influence each child’s individual experience.
New and Expectant Parents
Trisomy 9
This book is a resource to help you understand trisomy 9 and the unique details of pregnancy, delivery, and after-care. Let this guide empower you with accurate information and clarify the options you have going forward.
Includes a birth plan & after-care workbook to help prepare your family and your medical team
Parent Resources
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Create a Birth Plan
This will give you a way to communicate your needs and desires to your physician. It will help you know that your medical team is on the same page with you regarding your baby’s delivery and the level medical intervention you feel is best for your baby.
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Trisomy 9 Mosaic Syndrome
This article is a medical research review that looks at Trisomy 9 mosaic syndrome across many children and families. It helps explain why symptoms, development, and health needs can vary so widely, and outlines common medical findings doctors may monitor over time.
Please note: this is a technical article written for medical professionals and may feel detailed or clinical.
Mackenzie’s Story: A Trisomy 9 Mosaic Case Study
This resource shares one child’s experience with Trisomy 9 mosaic syndrome through a detailed case study. It follows Mackenzie from diagnosis in infancy through early childhood and highlights medical, developmental, and family context over time.
Please note: this is one individual case and is not meant to predict outcomes for other children.
Duplications of Trisomy 9p
This resource provides an overview of chromosome 9p duplications, a rare chromosome condition involving extra genetic material from chromosome 9. It explains what a duplication is, how size and location can vary, and what families may see in terms of health and development.
Please note: this is an educational information sheet written for families and professionals and includes medical and genetic terminology.
Luka’s Story: A Partial Trisomy 9 Case Study
This case study shares one child’s experience with partial Trisomy 9, beginning with a prenatal diagnosis and following early infancy. It provides insight into early medical considerations and family context during the first months of life.
Please note: this is one individual case and is not meant to predict outcomes for other children.
Prenatal Testing Resource Guide
Learn how different tests like the NIPT and amniocentesis can help you learn more about your baby’s health. Our guide explains everything in simple terms, including when these tests happen and what they involve.
