Related Experiment Video

Updated: Jul 21, 2026

Spectral Karyotyping to Study Chromosome Abnormalities in Humans and Mice with Polycystic Kidney Disease
12:47

Spectral Karyotyping to Study Chromosome Abnormalities in Humans and Mice with Polycystic Kidney Disease

Published on: February 3, 2012

Ring chromosome 2 in a child with growth failure and few congenital abnormalities

N V Vigfusson, K J Kapstafer, M A Lloyd

    American Journal of Medical Genetics
    |January 1, 1980
    PubMed

    Insights

    A rare ring chromosome 2 mosaic was identified in a newborn female experiencing severe growth issues. Despite the chromosomal abnormality, her psychomotor development remained normal up to 19 months old.

    Area of Science:

    • Genetics
    • Developmental Biology
    • Human Chromosome Research

    Background:

    • Mosaicism involving ring chromosomes can lead to variable clinical presentations.
    • Ring chromosome 2 is a rare chromosomal abnormality.
    • Understanding the origin and impact of mosaic chromosomal abnormalities is crucial for genetic counseling.

    Observation:

    • A newborn female presented with severe intrauterine growth retardation (IUGR) and postnatal growth failure.
    • She exhibited minor physical abnormalities.
    • A mosaic karyotype of 46,XX/46,XX,r(2)(p25q37) was detected, with the ring chromosome 2 present in 77.8% of cells.

    Findings:

    • G- and R-banding confirmed the breakpoints of the ring chromosome 2 at p25 and q37.
    • The ring chromosome 2 was de novo, absent in parents and sibling.
    • The presence of a normal cell line (46,XX) suggested the abnormality occurred post-conception.

    Implications:

    • This case highlights the occurrence of ring chromosome 2 mosaicism and its association with significant growth deficits.
    • The normal psychomotor development in the infant suggests that the impact of this specific ring chromosome 2 mosaicism may vary.
    • Further research is needed to elucidate the long-term outcomes and developmental trajectory in individuals with ring chromosome 2 mosaicism.

    More Related Videos

    Chromosome Preparation From Cultured Cells07:42

    Chromosome Preparation From Cultured Cells

    Published on: January 28, 2014

    Array Comparative Genomic Hybridization (Array CGH) for Detection of Genomic Copy Number Variants09:16

    Array Comparative Genomic Hybridization (Array CGH) for Detection of Genomic Copy Number Variants

    Published on: February 21, 2015

    Related Concept Videos

    Meiosis I01:49

    Meiosis I

    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...
    Karyotyping01:17

    Karyotyping

    Describing the number and physical features of chromosomes can reveal abnormalities that underlie genetic diseases. This description is facilitated by special staining techniques that produce a particular banding pattern on each chromosome. State-of-the-art techniques make this approach even more powerful, enabling the detection of individual genes that cause disease.A Simple Chromosome Staining Technique Provides Valuable Scientific InsightSome genetic diseases can be detected by looking at...
    Nondisjunction01:29

    Nondisjunction

    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.
    Karyotyping01:17

    Karyotyping

    Describing the number and physical features of chromosomes can reveal abnormalities that underlie genetic diseases. This description is facilitated by special staining techniques that produce a particular banding pattern on each chromosome. State-of-the-art techniques make this approach even more powerful, enabling the detection of individual genes that cause disease.A Simple Chromosome Staining Technique Provides Valuable Scientific InsightSome genetic diseases can be detected by looking at...
    Nondisjunction01:29

    Nondisjunction

    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.
    Nondisjunction01:21

    Nondisjunction

    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 sister...