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A family with syndactyly type II (synpolydactyly)
Clinical Genetics
|October 1, 1977
Summary
Syndactyly Type II, a genetic malformation, presents varied gene expression across four generations. Diagnostic features and linkage data for Syndactyly II were analyzed, revealing no close link to common blood group genes.
Area of Science:
- Medical Genetics
- Human Genetics
- Clinical Delineation
Background:
- Syndactyly Type II, also known as)'Poland anomaly', is a congenital malformation characterized by webbing of the fingers or toes.
- This study investigates the genetic basis and clinical presentation of Syndactyly Type II within a large, multi-generational family.
Observation:
- Eight family members across four generations exhibited Syndactyly Type II.
- Two distinct patterns of gene expression variation were observed among affected individuals.
- Severe manifestations of the malformation were associated with distorted dermatoglyphic patterns, unlike milder cases.
Findings:
- Linkage analysis indicated that the gene responsible for Syndactyly II is not closely linked to the loci for ABO, MNSs, P, Rh, and Kell blood group systems.
- The study discusses the diagnostic significance of identifying minimal clinical features of Syndactyly Type II.
Implications:
- Understanding the variable gene expression in Syndactyly Type II can aid in more accurate diagnosis and genetic counseling.
- The findings contribute to the genetic mapping of Syndactyly Type II, excluding linkage to several common blood group loci.
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