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Ring chromosome 7 and sacral agenesis
L Rodríguez1, A Sanchís, A Villa
1ECEMC, Facultad de Medicina, Universidad Complutense, Madrid, Spain.
American Journal of Medical Genetics
|September 12, 2000
Summary
A ring chromosome 7 was identified in a young girl with microcephaly and developmental delays. This case links ring chromosome 7 to sacral agenesis, a previously undescribed association, via genetic region loss.
Area of Science:
- Genetics
- Clinical Genetics
- Human Genetics
Background:
- Ring chromosome 7 is a rare chromosomal abnormality.
- Sacral agenesis is often associated with terminal 7q deletions, specifically involving the 7q36 region.
- The association between ring chromosome 7 and sacral agenesis has not been previously documented.
Observation:
- A 19-month-old female presented with microcephaly, growth and developmental delay, multiple angiomas, and partial sacral agenesis.
- High-resolution G-banding and fluorescence in situ hybridization (FISH) were performed.
- Genetic analysis revealed a ring chromosome 7.
Findings:
- The patient's ring chromosome 7 formation resulted in the loss of the 7q36 region.
- This loss explains the presence of sacral agenesis in the patient.
- This finding establishes a novel link between ring chromosome 7 and sacral agenesis.
Implications:
- This case expands the phenotypic spectrum associated with ring chromosome 7.
- It highlights the importance of genetic analysis in understanding complex congenital anomalies.
- Further research may elucidate the specific genes within 7q36 responsible for sacral development and their role in ring chromosome disorders.
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