Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Search research articles

Related Experiment Videos

Recurrent trisomy 21: four cases in three generations.

J L Gair¹, L Arbour, R Rupps

¹Department of Medical Genetics, University of British Columbia, Vancouver, BC, Canada.

Clinical Genetics

|October 7, 2005

Summary

This study reports four cases of Down syndrome (free trisomy 21) across three generations in one family, suggesting a potential inherited genetic factor. Researchers identified a possible cryptic rearrangement on chromosome 21, increasing non-disjunction risk.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

[GLI1 rearrangement in colon tumor: report of a case].

Zhonghua bing li xue za zhi = Chinese journal of pathology·2026

Same author

[Analysis of risk factors for early death in NPM1-mutated acute myeloid leukemia patients].

Zhonghua xue ye xue za zhi = Zhonghua xueyexue zazhi·2026

Same author

Nivolumab plus ipilimumab versus sunitinib for first-line treatment of advanced renal cell carcinoma: final analysis of efficacy and safety from the phase III CheckMate 214 trial.

Annals of oncology : official journal of the European Society for Medical Oncology·2026

Same author

Systematic curation and analysis of ovarian cancer data across multiple electronic record systems held within the UK National Health Service: a tertiary referral centre experience.

ESMO real world data and digital oncology·2026

Same author

[Healthcare institution resilience and the influencing factors during infectious disease outbreaks].

Beijing da xue xue bao. Yi xue ban = Journal of Peking University. Health sciences·2025

Same author

Retraction Note: MTA1 modulated by miR-30e contributes to epithelial-to-mesenchymal transition in hepatocellular carcinoma through an ErbB2-dependent pathway.

Oncogene·2025

Area of Science:

Genetics
Human Genetics
Reproductive Genetics

Background:

Recurrence of trisomy 21 (T21) is typically attributed to gonadal mosaicism in a single couple.
The occurrence of free T21 in multiple, unrelated individuals within a single family pedigree is rare.

Observation:

An unusual pedigree presented with four instances of Down syndrome (DS) due to free T21.
Affected individuals were born to four different mothers across three generations of the same family.
Mothers' ages at birth ranged from 18 to approximately 30 years.

Findings:

Microsatellite analysis excluded most of chromosome 21, identifying shared regions 21q11.1 and 21q22.3 among mothers.
Two family members, including a DS mother with a normal karyotype, possessed supernumerary alleles in the 21pter-21q11.1 region.

Related Experiment Videos

FISH analysis ruled out cryptic centromeric translocations involving chromosome 21, except possibly with chromosome 13.

An unusually high level of meiotic recombination on chromosome 21 was observed in this family.

Implications:

A cryptic rearrangement in the 21q11.1 region is hypothesized to disrupt chromosome pairing.
This disruption may lead to an elevated risk of chromosome 21 non-disjunction within the family.
The findings highlight the potential for familial predisposition to trisomy 21 beyond gonadal mosaicism.