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Partial trisomy 14q due to maternal t(4;14)(p16;q32) in a dysmorphic newborn
1Erciyes University, Medical Faculty, Department of Genetics, Kayseri, Turkey. munisdundar@gmail.com
Genetic Counseling (Geneva, Switzerland)
|October 28, 2011
Summary
This study reports a rare case of partial trisomy 14q in a newborn boy, identified through cytogenetic analysis and FISH. The condition resulted from a balanced maternal translocation, leading to specific dysmorphic features.
Area of Science:
- Genetics
- Clinical Genetics
- Human Genetics
Background:
- Partial trisomy 14q is a rare chromosomal abnormality often arising from parental translocations.
- Understanding the genetic basis of rare chromosomal disorders is crucial for diagnosis and genetic counseling.
Observation:
- A newborn male presented with dysmorphic features consistent with partial trisomy 14q.
- Cytogenetic analysis revealed an extra chromosomal segment on chromosome 4.
- Subtelomeric FISH confirmed the origin of the extra segment.
Findings:
- The patient's karyotype was determined as 46,XY, der(4)t(4;14)(p16;q32).
- This resulted from a balanced maternal translocation: 46,XX, t(4;14)(p16;q32).
- The findings confirm a diagnosis of partial trisomy 14q.
Implications:
- This case contributes to the understanding of partial trisomy 14q and its phenotypic manifestations.
- Accurate karyotyping is essential for diagnosing such rare chromosomal disorders.
- Identifying parental translocations is key for genetic counseling and recurrence risk assessment.
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