X-linked dominant
WikiDoc Resources for X-linked dominant |
Articles |
---|
Most recent articles on X-linked dominant Most cited articles on X-linked dominant |
Media |
Powerpoint slides on X-linked dominant |
Evidence Based Medicine |
Cochrane Collaboration on X-linked dominant |
Clinical Trials |
Ongoing Trials on X-linked dominant at Clinical Trials.gov Trial results on X-linked dominant Clinical Trials on X-linked dominant at Google
|
Guidelines / Policies / Govt |
US National Guidelines Clearinghouse on X-linked dominant NICE Guidance on X-linked dominant
|
Books |
News |
Commentary |
Definitions |
Patient Resources / Community |
Patient resources on X-linked dominant Discussion groups on X-linked dominant Patient Handouts on X-linked dominant Directions to Hospitals Treating X-linked dominant Risk calculators and risk factors for X-linked dominant
|
Healthcare Provider Resources |
Causes & Risk Factors for X-linked dominant |
Continuing Medical Education (CME) |
International |
|
Business |
Experimental / Informatics |
Please Take Over This Page and Apply to be Editor-In-Chief for this topic: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [1] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.
Overview
X-linked dominant is mode of inheritance in which a gene on the X chromosome is dominant.[1] Females can be more frequently affected than males since they have two X chromosomes that could potentially carry the abnormal gene, whereas a male has only one. However, the Lyon hypothesis states that X-inactivation renders only one copy of the X chromosome active in each cell hence on average one would expect only one half of the cells to express the abnormal gene. The chance of passing on an X-linked dominant disorder differs between men and women.
As a disease inheritance pattern, it is less common than X-linked recessive.
Inheritance
Females usually have two X chromosomes, while most males have one X and one Y chromosome. If a child has inherited the mutation from the X chromosome of one of their parents they will have the condition. A woman with an X-linked dominant disorder has a 50% chance of having an affected daughter or son with each pregnancy. The sons of a man with an X-linked dominant disorder will not be affected (since they inherit their only X chromosome from their mother), but his daughters will all inherit the condition.
-
A woman with an X-linked dominant disorder has a 50% chance of having an affected child.
-
The daughters of a man with an X-linked dominant disorder will all inherit the condition.
Some X-linked dominant conditions such as Aicardi Syndrome are fatal to boys, therefore only girls with these conditions survive. Similarly, individuals with Klinefelter's Syndrome are referred to as "47,XXY Males".