October 21, 2016
font size

Definition of Paracentric chromosome inversion

Paracentric chromosome inversion: A basic type of chromosome rearrangement. A segment that does not include the centromere (and so is paracentric) has been snipped out of a chromosome, turned through 180 degrees (inverted), and inserted right back into its original location in chromosome. The feature that makes it paracentric is that both breaks are on the same side of the centromere so that the centromere (the point at which the chromosome attaches to the spindle) is not affected.

Any chromosome inversion can be inherited and have come from one of the parents to a child. Or the inversion can appear for the first time in a child.

An inversion can be "balanced," meaning that it has all the genes present in the normal uninverted chromosome. Or an inversion can be "unbalanced," meaning that genes been have deleted (lost) or duplicated.

A balanced inversion in a child causes no problems. An unbalanced inversion is abnormal and is often associated with problems such as development delay (and later, mental retardation) and multiple congenital anomalies (birth defects).

Inversions can also be acquired in a body cell (a somatic cell) and in the process, disrupt a gene. This can be a step involving that cell in a precancerous and cancerous process.

Source: MedTerms™ Medical Dictionary
Last Editorial Review: 10/30/2013

Drug Medical Dictionary of Terms by Letter

Top RxList Drug News

Use Pill Finder Find it Now See Interactions

Pill Identifier on RxList

  • quick, easy,
    pill identification

Find a Local Pharmacy

  • including 24 hour, pharmacies

Interaction Checker

  • Check potential drug interactions
Search the Medical Dictionary for Health Definitions & Medical Abbreviations