Recombinational event between Norrie disease and DXS7 loci
J T Ngo1, M A Spence, V Cortessis
1Jules Stein Eye Institute, Department of Ophthalmology, UCLA School of Medicine.
Clinical Genetics
|July 1, 1988
Summary
Researchers identified a family with X-linked Norrie disease, revealing a recombination event near the DXS7 locus. This finding suggests the L1.28 probe is useful but not entirely reliable for prenatal diagnosis of Norrie disease.
Area of Science:
- Genetics
- Molecular Biology
- Ophthalmology
Background:
- Norrie disease is a rare X-linked recessive disorder affecting vision.
- Genetic linkage analysis is crucial for understanding disease inheritance patterns.
Purpose of the Study:
- To investigate a family with X-linked Norrie disease and analyze a potential recombinational event.
- To evaluate the utility of the L1.28 probe for Norrie disease gene localization and prenatal diagnosis.
Main Methods:
- Genetic analysis of an affected family.
- Linkage analysis using the L1.28 probe at the DXS7 locus.
- Calculation of lod scores and recombination frequencies.
Main Results:
- A recombinational event was identified between the Norrie disease locus and the DXS7 locus (probe L1.28).
- A maximum lod score of 7.58 at a recombination frequency of 0.038 +/- 0.036 was achieved with seven informative families.
- The L1.28 probe is useful but not completely reliable for prenatal diagnosis.
Conclusions:
- The gene for Norrie disease is not located within the DNA sequence identified by the L1.28 probe.
- Further studies are needed to precisely map the Norrie disease gene.
- The L1.28 probe has limited but potential utility in prenatal diagnosis for specific families.
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