What is chromosome Xp22?

Abstract. The Xp22. 31 segment of the short arm of the human X chromosome is a region of high instability with frequent rearrangement. The duplication of this region has been found in healthy people as well as in individuals with varying degrees of neurological impairment.

What does chromosome duplication do?

The term “duplication” simply means that a part of a chromosome is duplicated, or present in 2 copies. This results in having extra genetic material, even though the total number of chromosomes is usually normal.

Is chromosomal duplication harmful?

Neofunctionalization. Gene duplications are an essential source of genetic novelty that can lead to evolutionary innovation. Duplication creates genetic redundancy, where the second copy of the gene is often free from selective pressure—that is, mutations of it have no deleterious effects to its host organism.

What happens after chromosome duplication?

The process of creating two new cells begins once a cell has duplicated its chromosomes. In this state each chromosome consists of a joined pair of identical replicas called chromatids. The chromosomes condense and line up across the center of the nucleus. The membrane surrounding the nucleus fragments and disappears.

What disease does duplication cause?

MECP2 duplication syndrome is a condition that occurs almost exclusively in males and is characterized by moderate to severe intellectual disability. Most people with this condition also have weak muscle tone in infancy, feeding difficulties, poor or absent speech, or muscle stiffness (rigidity).

Is gene duplication good or bad?

Duplicate genes are not only redundant, but they can be bad for cells. Most duplicate genes accumulate mutations at high rates, which increases the chance that the extra gene copies will become inactive and lost over time due to natural selection.

What happens during duplication?

​Duplication Duplication is a type of mutation that involves the production of one or more copies of a gene or region of a chromosome. Gene and chromosome duplications occur in all organisms, though they are especially prominent among plants. Gene duplication is an important mechanism by which evolution occurs.

Can duplication syndrome be inherited?

In most cases, MECP2 duplication syndrome is inherited from a mother who carries the duplication but has no symptoms. Rarely, the condition is not inherited. In these cases it may occur randomly during the formation of the egg or sperm, or shortly after the egg and sperm join together.

How big is the xp22.31 microduplication in patients?

The size of the Xp22.31 duplications ranged from 294 kb to 1.6 Mb. We show a comparison of the breakpoints, inheritance and clinical phenotype, and a review of the literature. This clinically detailed series of Xp22.31 duplication patients provides evidence that the Xp22.31 duplication contributes to a common phenotype.

Which is a common phenotype of xp22.31?

This clinically detailed series of Xp22.31 duplication patients provides evidence that the Xp22.31 duplication contributes to a common phenotype. Keywords: chromosomal duplication; copy-number; developmental delay; epilepsy; seizures; talipes.

Are there any cases of Xp22.2 deletion?

PMID: 26676689 Free PMC Article Familial cases of a submicroscopic Xp22.2 deletion: genotype-phenotype correlation in microphthalmia with linear skin defects syndrome. Mol Vis 2013;19:311-8.

Can a terminal XP deletion cause linear skin defects?

Mother and daughter with a terminal Xp deletion: implication of chromosomal mosaicism and X-inactivation in the high clinical variability of the microphthalmia with linear skin defects (MLS) syndrome. Eur J Med Genet 2007 Nov-Dec;50 (6):421-31. Epub 2007 Aug 6 doi: 10.1016/j.ejmg