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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...

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Sirenomelia: adding something new.

¹Department of Paediatric Surgery, The Children's Hospital and the Institute of Child Health Lahore, Pakistan.

Journal of Neonatal Surgery

|May 30, 2015

Summary

This summary is machine-generated.

This report details a rare case of sirenomelia, a congenital anomaly, observed in one twin. The affected infant presented with a fused lower torso, highlighting the diverse anatomical outcomes in twin pregnancies.

Keywords:

Mermaid syndrome Sirenomelia Twins Variant

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Area of Science:

Medical Science
Genetics
Developmental Biology

Background:

Sirenomelia, or mermaid syndrome, is a rare congenital anomaly characterized by the fusion of the lower extremities.
It is often associated with other anomalies and has a high mortality rate.
Twin pregnancies present unique challenges in prenatal diagnosis and management.

Observation:

A case of sirenomelia was observed in a twin pregnancy.
The affected fetus exhibited a significantly different anatomy of the lower torso compared to its twin.
Detailed anatomical examination revealed the characteristic features of sirenomelia.

Findings:

The reported case confirms the occurrence of sirenomelia in the context of a twin pregnancy.
Variations in lower torso anatomy were noted between the twins.
This case adds to the understanding of sirenomelia's presentation in multifetal gestations.

Implications:

Understanding sirenomelia in twin pregnancies is crucial for accurate prenatal diagnosis and counseling.
Further research into the genetic and environmental factors contributing to sirenomelia in twins is warranted.
This case highlights the importance of detailed anatomical assessment in twin pregnancies to identify congenital anomalies.