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FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
Klinefelter variant mosaic with a reciprocal translocation t(1;7)
Vidya Vasu1, Nallathambi Chandra, Meena Jayashankar
1Department of Genetics, Dr ALM PG Institute of Basic Medical Sciences, University of Madras, Taramani, Chennai, India.
Fertility and Sterility
|February 29, 2008
Summary
This case report details a male patient diagnosed with Klinefelter syndrome, revealing a complex karyotype with a rare translocation. The findings highlight the importance of cytogenetic analysis for accurate diagnosis and management of genetic disorders.
Area of Science:
- Human Genetics
- Clinical Cytogenetics
- Reproductive Biology
Background:
- Klinefelter syndrome is a common genetic condition affecting males, typically characterized by the presence of an extra X chromosome (47,XXY).
- Accurate karyotyping is crucial for diagnosing Klinefelter syndrome and understanding its genetic basis.
- Genetic translocations can complicate karyotypes and may influence reproductive outcomes.
Observation:
- A male patient with a provisional diagnosis of Klinefelter syndrome underwent chromosomal analysis.
- Conventional cytogenetic techniques were employed on peripheral blood lymphocytes.
- The analysis aimed to determine the constitutional karyotype and assess hormonal profiles.
Findings:
- The patient's karyotype was identified as mosaic 48,XXXY,t(1;7)(q42;q32)pat[71%]/47,XXY,t(1;7)(q42;q32)pat[29%].
- This represents the first reported case of this specific complex karyotype.
- The patient's father and brother were carriers of the same translocation (46,XY,t(1;7)(q42;q32)).
Implications:
- The findings suggest that alternate segregation of the t(1;7) translocation during spermatogenesis may lead to meiotic nondisjunction.
- This supports the hypothesis of an interchromosomal effect in genetic disorders.
- The study underscores the clinical significance of cytogenetic diagnosis for improved management of genetic conditions.
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