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

Related Concept Videos

Pleiotropy

Pleiotropy

Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause Waardenburg Syndrome Type 4, or WS4, which can cause defects in pigmentation, hearing impairments, and an absence of intestinal contractions necessary for elimination. This diversity of phenotypes results from the expression pattern of SOX10 in early embryonic and fetal development. SOX10 is found in neural crest cells that form melanocytes,...

Gene Duplication and Divergence

Gene Duplication and Divergence

The seminal work of Ohno in 1970 popularized the idea of gene duplication and divergence. DNA sequence comparison studies reveal that a large portion of the genes in bacteria, archaebacteria, and eukaryotes was generated by gene duplication and divergence, indicating its critical role in evolution.
The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.

X-linked Traits

X-linked Traits

In most mammalian species, females have two X sex chromosomes and males have an X and Y. As a result, mutations on the X chromosome in females may be masked by the presence of a normal allele on the second X. In contrast, a mutation on the X chromosome in males more often causes observable biological defects, as there is no normal X to compensate. Trait variations arising from mutations on the X chromosome are called “X-linked”.

X-linked Traits

X-linked Traits

In most mammalian species, females have two X sex chromosomes and males have an X and Y. As a result, mutations on the X chromosome in females may be masked by the presence of a normal allele on the second X. In contrast, a mutation on the X chromosome in males more often causes observable biological defects, as there is no normal X to compensate. Trait variations arising from mutations on the X chromosome are called “X-linked”.

Exon Recombination

Exon Recombination

The evolution of new genes is critical for speciation. Exon recombination, also known as exon shuffling or domain shuffling, is an important means of new gene formation. It is observed across vertebrates, invertebrates, and in some plants such as potatoes and sunflowers. During exon recombination, exons from the same or different genes recombine and produce new exon-intron combinations, which might evolve into new genes.
Exon shuffling follows “splice frame rules.” Each exon has three reading...

Chromosome Duplication

Chromosome Duplication

The process of chromosome duplication during cell division requires genome-wide disruption and re-assembly of chromatin. The chromatin structure must be accurately inherited, reassembled, and maintained in the daughter cells to ensure lineage propagation.
The basic unit of the chromatin is the nucleosome, consisting of DNA wrapped around octameric histone proteins and short stretches of linker DNA separating individual nucleosomes. The histone proteins within the nucleosome have their...

You might also read

Related Articles

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

Sort by

Same author

Papular telangiectasias in hereditary haemorrhagic telangiectasia.

The British journal of dermatology·2026

Same author

Sirolimus for Extracranial Arteriovenous Malformations: A Scoping Review of the Evidence in Syndromic and Non-Syndromic Cases.

Pediatric blood & cancer·2026

Same author

Challenging interpretation of low-level PTCH1 mosaicism in patients with clinically diagnosed Gorlin syndrome: a case series and review of the literature.

Hereditary cancer in clinical practice·2026

Same author

Systematic review of cardiovascular intervention studies in women after Preeclampsia.

Pregnancy hypertension·2026

Same author

Urothelial Carcinoma of the Penile Urethra as a Potential Secondary Complication of Junctional Epidermolysis Bullosa: A Case Report and Review of the Literature.

Case reports in dermatological medicine·2026

Same author

A tale of two KRAS variants.

The British journal of dermatology·2026

Search research articles

Related Experiment Video

Updated: May 19, 2026

In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila

In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila

Published on: August 20, 2019

Phenotype in novel Xp duplication.

Manju Salaria¹, Trent Burgess, Stella Setyapranata

¹Genetic Medicine, Royal Melbourne Hospital, Parkville, Victoria, Australia.

American Journal of Medical Genetics. Part A

|August 14, 2012

Summary

This summary is machine-generated.

A novel Xp duplication was identified in a man with ichthyosis and hypogonadotropic hypogonadism. This genetic finding in Xp22.31p22.2 provides new insights into X chromosome duplications and their associated phenotypes.

More Related Videos

Generation and Characterization of Human Induced Pluripotent Stem Cell-derived Astrocytes Lacking Fragile X Messenger Ribonucleoprotein

Generation and Characterization of Human Induced Pluripotent Stem Cell-derived Astrocytes Lacking Fragile X Messenger Ribonucleoprotein

Published on: June 6, 2025

A Non-random Mouse Model for Pharmacological Reactivation of Mecp2 on the Inactive X Chromosome

A Non-random Mouse Model for Pharmacological Reactivation of Mecp2 on the Inactive X Chromosome

Published on: May 22, 2019

Related Experiment Videos

Last Updated: May 19, 2026

In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila

In Vivo Functional Study of Disease-associated Rare Human Variants Using Drosophila

Published on: August 20, 2019

Generation and Characterization of Human Induced Pluripotent Stem Cell-derived Astrocytes Lacking Fragile X Messenger Ribonucleoprotein

Generation and Characterization of Human Induced Pluripotent Stem Cell-derived Astrocytes Lacking Fragile X Messenger Ribonucleoprotein

Published on: June 6, 2025

A Non-random Mouse Model for Pharmacological Reactivation of Mecp2 on the Inactive X Chromosome

A Non-random Mouse Model for Pharmacological Reactivation of Mecp2 on the Inactive X Chromosome

Published on: May 22, 2019

Area of Science:

Human Genetics
Genomics
Medical Genetics

Background:

X chromosome duplications are rare genetic alterations.
Understanding the phenotypic consequences of specific X chromosome duplications is crucial for genetic diagnostics.
The Xp22.31p22.2 region is implicated in various developmental processes.

Observation:

A 20-year-old male presented with ichthyosis, congenital heart defect, varicose veins, and hypogonadotropic hypogonadism.
This patient was found to have an interstitial duplication of approximately 2.8 Mb in the Xp22.31p22.2 region.
The same duplication was identified in his similarly affected brother and in their asymptomatic mother.

Findings:

Identification of a novel interstitial duplication in chromosome region Xp22.31p22.2.
Correlation of this specific Xp duplication with a distinct set of clinical anomalies.
Evidence of familial inheritance of the Xp duplication, with variable expressivity.

Implications:

This study expands the known spectrum of phenotypes associated with X chromosome duplications.
The findings contribute to a better understanding of the genetic basis of hypogonadotropic hypogonadism and ichthyosis.
Characterization of this Xp duplication provides valuable data for genetic counseling and diagnosis of similar cases.