Related Experiment Video
Updated: Mar 22, 2026
07:34
FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
38.0K
Anatomy of trisomy 12
Wallisa Roberts1, Anna Zurada2, Agnieszka Zurada-ZieliŃSka2
1Department of Anatomical Sciences, St George's University, Grenada, West Indies.
Clinical Anatomy (New York, N.Y.)
|April 19, 2016
Summary
Trisomy 12, a genetic abnormality involving chromosome 12 duplication, occurs in 1 in 500 live births due to mosaicism. Variable phenotypes necessitate increased medical awareness and further documentation for specific types like trisomy 12q.
Area of Science:
- Genetics
- Developmental Biology
- Medical Anatomy
Background:
- Trisomy 12 is a rare aneuploidy, often leading to spontaneous abortion.
- Mosaicism allows trisomy 12 to present in live births, occurring at a rate of 1 in 500.
- Medical practitioners require awareness of this aneuploidy due to its incidence.
Purpose of the Study:
- To review common anatomical variations associated with different types of trisomy 12.
- To highlight the need for further documentation of specific trisomy 12 subtypes.
Main Methods:
- Literature review focusing on anatomical variations in trisomy 12.
- Analysis of existing documentation on trisomy 12 phenotypes.
Main Results:
- Trisomy 12 can result from complete or partial duplication of chromosome 12.
- Mosaicism and variable duplication sites lead to a wide spectrum of phenotypes.
- Significant variability exists in phenotypes, ranging from normal to severe defects.
Conclusions:
- Further documentation is essential for trisomy 12q and complete trisomy 12.
- Clear delineation of anomalies characterizing each genetic defect is needed.
- Enhanced understanding of trisomy 12 phenotypes is crucial for medical practice.
More Related Videos
Related Concept Videos
01:49Meiosis I
221.5K
Meiosis is a carefully orchestrated set of cell divisions, the goal of which—in humans—is to produce haploid sperm or eggs, each containing half the number of chromosomes present in somatic cells elsewhere in the body. Meiosis I is the first such division, and involves several key steps, among them: condensation of replicated chromosomes in diploid cells; the pairing of homologous chromosomes and their exchange of information; and finally, the separation of homologous chromosomes by...
221.5K
01:17Karyotyping
69.8K
Overview
69.8K
01:17Karyotyping
11.9K
11.9K
01:21Nondisjunction
5.6K
Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate correctly and move to the opposite poles of the cells. This produces daughter cells with abnormal chromosome numbers. Nondisjunction is common during anaphase I or anaphase II of meiosis. Mutations in synaptonemal complex proteins that attach homologous chromosomes increase the chances of nondisjunction in anaphase I of meiosis I. In contrast, mutations in topoisomerases and condensins that hold...
5.6K
01:29Nondisjunction
83.3K
During meiosis, chromosomes occasionally separate improperly. This occurs due to failure of homologous chromosome separation during meiosis I or failed sister chromatid separation during meiosis II. In some species, notably plants, nondisjunction can result in an organism with an entire additional set of chromosomes, which is called polyploidy. In humans, nondisjunction can occur during male or female gametogenesis and the resulting gametes possess one too many or one too few chromosomes.
83.3K
02:04Polytene Chromosomes
11.3K
Polytene chromosomes are giant interphase chromosomes with several DNA strands placed side by side. They were discovered in the year 1881 by Balbiani in salivary glands, intestine, muscles, malpighian tubules, and hypoderm of larvae Chironomus plumosus. Hence, these are also called "Salivary gland chromosomes." These are found in insects of the order Diptera and Collembola; in certain organs of mammals; and synergids, antipodes of flowering plants. Polytene chromosomes are also...
11.3K