Title: XXX Syndrome
Author: Harold Chen, MD, Medical Genetics, Shriners Hospitals for Children & LSU Health Sciences Center, Shreveport, LA, USA
Source: In: Atlas of Genetic Diagnosis and Counseling, Springer Nature (2017), pp. 3045–3050 (link.springer.com)
DOI: 10.1007/978‑1‑4939‑2401‑1_251
Citation: Chen, H. (2017). XXX Syndrome. In: Atlas of Genetic Diagnosis and Counseling. Springer, New York, NY. https://doi.org/10.1007/978-1-4939-2401-1_251
🔍 Background & Objectives
This reference entry provides a comprehensive overview of 47,XXX syndrome (Trisomy X)—a chromosomal condition affecting approximately 1 in 1,000 female births. Although often underdiagnosed, understanding its clinical spectrum is crucial for genetic counseling and management.
🧬 Key Data & Facts
- First documented by Jacobs in 1979.
- Occurs in ~0.1% of live female births; however, only about 10% are clinically diagnosed due to mild or asymptomatic presentations (link.springer.com, researchgate.net).
- Recognized as the most common female sex chromosome anomaly.
📚 Clinical Presentation
- Phenotypic variability spans from asymptomatic to features including tall stature, minor congenital anomalies, cognitive and language delays, and reproductive irregularities.
- Associated developmental concerns are detailed through phenotype examples and epidemiological data.
🧠 Implications for Practice
- Early recognition via prenatal karyotyping can guide surveillance and intervention.
- Highlights the need for tailored genetic and developmental follow-up due to range in severity.
⚠️ Limitations & Notes
- Content based on review literature; individual variation can be significant.
- Emphasizes importance of professional genetic consultation for accurate diagnosis and guidance.
📌 Conclusion
Dr. Harold Chen’s entry on XXX syndrome is a definitive, well‑structured resource summarizing prevalence, presentation, and clinical considerations—essential for geneticists, pediatricians, and counselors handling chromosomal conditions.