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Meiosis I

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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 a...

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Nondisjunction

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FISH for Pre-implantation Genetic Diagnosis

FISH for Pre-implantation Genetic Diagnosis

Published on: February 23, 2011

Mosaic trisomy 13 and a sacral appendage.

Harry Pachajoa¹, Luis Enrique Meza Escobar

¹Faculty of Medicine, Universidad Icesi, Cali, Valle del Cauca, Colombia. hmpachajoa@icesi.edu.co

BMJ Case Reports

|August 2, 2013

Summary

This summary is machine-generated.

Mosaic trisomy 13, a genetic condition with varying severity, involves some cells having an extra chromosome 13. This case highlights a patient with less severe symptoms and unique features.

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Area of Science:

Genetics
Developmental Biology
Clinical Medicine

Background:

Mosaic trisomy 13 is a chromosomal disorder where a portion of cells exhibit an extra copy of chromosome 13.
It presents with a wide spectrum of clinical manifestations and variable severity compared to complete trisomy 13.
The prevalence is estimated between 1 in 10,000 and 1 in 20,000 births.

Observation:

This report details a case of mosaic trisomy 13.
The patient presented with a sacral appendage and cleft lip and palate.
This specific presentation adds to the known phenotypic variability of the condition.

Findings:

Mosaic trisomy 13 patients generally experience longer survival and milder phenotypes than those with complete trisomy 13.
The genetic counseling for mosaic trisomy 13 is challenging due to the broad range of clinical outcomes.
This case contributes to the limited literature, with 49 previously reported cases.

Implications:

Understanding the phenotypic variability is crucial for accurate diagnosis and management of mosaic trisomy 13.
Further case reports are needed to better delineate the spectrum of this rare genetic disorder.
This case underscores the importance of detailed clinical observation in genetic syndromes.