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An unbalanced autosomal translocation (7;9) associated with feminization
M Crocker1, S B Coghill, R Cortinho
1Department of Medical Genetics, Churchill Hospital, Oxford, England.
Clinical Genetics
|July 1, 1988
Summary
A rare genetic condition involving chromosome 9p deletion in a newborn with XY chromosomes led to feminization and death. This suggests critical genes for testis formation are located on the 9p region.
Area of Science:
- Genetics
- Developmental Biology
- Pediatrics
Background:
- Genetic translocations can lead to unbalanced chromosomal abnormalities with significant clinical consequences.
- Understanding the genetic basis of sex determination and differentiation is crucial for diagnosing and managing disorders of sex development.
Observation:
- A newborn with generalized mild dysmorphic features presented with XY chromosomes but exhibited phenotypic characteristics inconsistent with typical male development.
- The infant developed severe complications including heart failure and hydrocephalus, succumbing at 5 months of age.
Findings:
- Chromosome analysis revealed an unbalanced reciprocal translocation, resulting in partial trisomy for 7q and partial monosomy for 9p (karyotype: 46,XY,-9,+der(9),t(7;9)(q31.1;p23)pat).
- The patient's father was identified as a balanced carrier of the reciprocal translocation (karyotype: 46,XY,(7;9)(q31.1;p23)).
- The observed feminization in an XY individual with 9p monosomy, in conjunction with prior reports, strongly implicates the 9p region in normal testis formation.
Implications:
- This case highlights the critical role of the 9p chromosomal region in male sex determination and testis development.
- Further research into the specific genes within the 9p region is warranted to elucidate their function in gonadal development.
- Accurate genetic diagnosis and counseling are essential for families carrying balanced translocations that could result in unbalanced offspring with disorders of sex development.