47,XYY affects about 1 in 1,000 males. Adding to its relative rarity, it is diagnosed in only about 10 percent of cases, often during prenatal testing.
Many with 47,XYY have no symptoms at all. Others can demonstrate significant developmental and behavioral issues.
47,XYY was sometimes referred to as “Jacob’s syndrome.”
47,XYY may produce a wide array of symptoms, although most people with the extra Y chromosome it entails will exhibit only some, but not all, of the following:
Low muscle tone
Speech delay/expressive language disorder
Subtle developmental delays
The Case for Testing
When children show a history of symptoms such as speech delay, learning disability, or autism, parents should strongly consider genetic testing to determine if the cause is a sex chromosome aneuploidy (SCA). Testing for 47,XYY involves a specialized blood test, either a “karyotyping” or a “microarray.” Health care professionals are often unfamiliar with the developmental and cognitive deficits associated with X & Y variations.
Downloadable Brochure- About 47,XYY Trifold brochure printing instructions: Be sure you are printing in two-sided (duplex) mode, and to select the “Flip on Short Edge” or “Short-Edge Binding” option, if available in the Print dialog box or any associated dialog boxes.
Thanks to the generosity of the book’s author, Virginia Isaac’s Cover, MSW, AXYS is pleased to make this book available to the X and Y variation community, in its entirety, at no cost. Please feel free to download and/or print it for your personal use. (Those wishing to purchase a soft-bound copy can do so at Amazon or Kindle. All proceeds from the sale of this book benefit AXYS.)