Related Experiment Videos
An expected decrease in the incidence of autosomal recessive disease due to decreasing consanguineous marriages.
1Department of Child Ecology, National Children's Medical Research Center, Tokyo, Japan.
Genetic Epidemiology
|January 1, 1988
Summary
Declining consanguineous marriages in Japan led to a significant decrease in autosomal recessive disorders. This trend, particularly noticeable in low gene frequency disorders, was observed between 1942 and 1983.
Area of Science:
- Population Genetics
- Medical Genetics
- Human Genetics
Background:
- Consanguineous marriages increase the risk of autosomal recessive disorders.
- A decline in consanguinity rates is expected to reduce the incidence of these genetic conditions.
Purpose of the Study:
- To theoretically estimate the chronological decrease in autosomal recessive disorder incidence in Japan.
- To assess the impact of declining consanguinity on genetic disorder rates from 1942 to 1983.
Main Methods:
- Utilized Hardy-Weinberg expectation for partially inbred populations.
- Applied literature-based consanguinity rates for chronological estimations.
- Employed Nei's extended Dahlberg's formula to estimate changes in first-cousin marriage proportions.
Main Results:
- Substantial decrease in autosomal recessive disorder incidence and first-cousin marriage proportions observed.
- The decline was more pronounced for disorders with lower gene frequencies.
- Estimated incidence reduction of 40-80% and a drop in first-cousin marriages from 40-70% to 5-15%.
Conclusions:
- The decline in consanguineous marriages has significantly reduced autosomal recessive disorder incidence in Japan.
- Theoretical estimates align well with observed data for phenylketonuria and Wilson's disease.
- This highlights the public health impact of changing marriage patterns on genetic disease prevalence.