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Klinefelter syndrome: are we missing opportunities for early detection?
Leena Nahata1, Ilina Rosoklija, Richard N Yu
11Boston Children's Hospital, Boston, MA, USA.
Insights
Klinefelter syndrome is often underdiagnosed in boys. Consider karyotyping for neurocognitive issues, as this condition frequently presents with learning disabilities and attention deficit disorder.
Area of Science:
- Pediatrics
- Genetics
- Endocrinology
Background:
- Klinefelter syndrome (KS) is a common genetic condition often diagnosed late.
- Classic physical signs may not appear until adolescence, delaying diagnosis and intervention.
- Current screening guidelines for KS are limited.
Purpose of the Study:
- To investigate the diagnostic patterns and common comorbidities of KS in children and adolescents.
- To identify potential indicators for earlier KS screening.
- To inform clinical practice regarding KS diagnosis in pediatric populations.
Main Methods:
- Retrospective chart review of patients diagnosed with KS before age 20 at Boston Children's Hospital.
- Analysis of diagnostic age, reasons for diagnosis, karyotype results, height data, and co-occurring conditions.
- Statistical evaluation of comorbidity prevalence and association with KS.
Main Results:
- Eighty percent of patients had the 47,XXY karyotype, with half diagnosed between ages 11-19.
- Neurocognitive comorbidities were most frequent: learning disabilities (67%), psychosocial problems (33%), and attention deficit disorder (27%).
- Children with KS showed only slight height deviations from average during childhood (SDS=0.64).
Conclusions:
- Klinefelter syndrome is frequently underdiagnosed and associated with significant, long-standing neurocognitive comorbidities.
- A karyotype evaluation should be considered in boys presenting with neurocognitive challenges.
- Early recognition of KS is crucial for timely management and prevention of associated health issues.
Abstract:
Klinefelter syndrome is a common condition that remains underdiagnosed, particularly prior to adulthood. Early detection could prevent morbidity and mortality, but the classic phenotype of small testes and tall stature may not be apparent until adolescence, and there is minimal guidance regarding whom to screen. We performed a retrospective study at Boston Children's Hospital in patients with the ICD-9 code for "Klinefelter syndrome" diagnosed prior to age 20 years, and determined age and reason for diagnosis, karyotype, heights, and comorbid conditions. Eighty percent had a 47,XXY karyotype, of whom half were diagnosed at age 11 to 19 years. The most common comorbidities were neurocognitive, including learning disabilities (67%), psychosocial problems (33%), and attention deficit disorder (27%). Subjects were only slightly taller than average in childhood (height standard deviation score = 0.64). These data show that Klinefelter syndrome is associated with long-standing comorbidities that frequently remain under-recognized; a karyotype should be considered in boys with neurocognitive problems.
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