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Semiconductor Sequencing for Preimplantation Genetic Testing for Aneuploidy
Published on: August 25, 2019
Growth profiles of human autosomal trisomies at midgestation
1Department of Pediatrics, University of Michigan, Ann Arbor 48109, USA.
Teratology
|December 1, 1994
Insights
Each trisomy (Down syndrome, Edwards syndrome, Patau syndrome) presents unique fetal growth patterns. These chromosomal disorders, including trisomy 21, 18, and 13, affect fetal development distinctively.
Area of Science:
- Medical genetics
- Developmental biology
- Human embryology
Background:
- Chromosomal abnormalities significantly impact fetal development.
- Trisomies 21, 18, and 13 are common aneuploidies with variable phenotypic outcomes.
- Understanding specific growth patterns aids in prenatal diagnosis and management.
Purpose of the Study:
- To characterize the distinct somatic and visceral growth profiles of human fetuses with trisomy 21, 18, and 13.
- To identify specific organ weight deviations associated with each trisomy.
- To correlate chromosomal abnormalities with characteristic fetal growth aberrations.
Main Methods:
- Comparative analysis of somatic and visceral growth parameters.
- Measurement of organ weights (limbs, adrenal glands, lungs, spleen, kidneys) in midgestation fetuses.
- Histopathological examination and morphometric analysis.
Main Results:
- Trisomy 21 fetuses exhibit characteristic short limb growth.
- Trisomy 18 fetuses show subnormal adrenal and lung weights.
- Trisomy 13 fetuses display supranormal spleen and kidney weights.
Conclusions:
- Each trisomy (21, 18, 13) has a unique growth signature.
- Specific organ weight deviations can serve as potential biomarkers for prenatal identification of trisomies.
- Detailed growth profiling enhances understanding of aneuploidy-associated developmental disturbances.
Abstract:
Somatic and visceral growth profiles of midgestation human fetuses with trisomy 21, 18, or 13 demonstrate that each disorder has a characteristic pattern of growth aberration. The most striking deviations are short limbs in trisomy 21, subnormal adrenal and lung weights in trisomy 18, and supranormal spleen and kidney weights in trisomy 13.
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