What is AZFc Microdeletion?
AZFc, the most frequently deleted region of the Y chromosome in infertile males, is a de-novo microdeletion found in one out of 4,000 males . Men with Y chromosome microdeletions and severe oligozoospermia or azoospermia are sometimes able to reproduce via assisted reproductive technology such as ICSI.
How common is Y chromosome deletion?
Prevalence. The prevalence of Y chromosome deletions and microdeletions is estimated at 1:2,000 to 1:3,000 males [de Vries et al 2002; de Vries et al, personal communication]. The frequency of Yq microdeletions in males with azoospermia or severe oligozoospermia is about 5% [Kim et al 2017].
What genetic disorder has a missing Y chromosome?
In males, the 23rd pair is one X and one Y chromosome. There are 2 types of Turner syndrome: monosomy X TS and mosaic TS. About half of all girls with Turner syndrome have a monosomy disorder. Monosomy means that a person is missing one chromosome in the pair.
Why does the Y chromosome degeneration?
This means that genes on the Y chromosome cannot undergo genetic recombination, the “shuffling” of genes that occurs in each generation which helps to eliminate damaging gene mutations. Deprived of the benefits of recombination, Y chromosomal genes degenerate over time and are eventually lost from the genome.
Is Y chromosome microdeletion genetic?
Y chromosome microdeletion (YCM) is a family of genetic disorders caused by missing gene(s) in the Y chromosome. Many men with YCM exhibit no symptoms and lead normal lives. However, YCM is also known to be present in a significant number of men with reduced fertility.
What are the AZF deletions on the Y chromosome?
Microdeletions of the long arm of the human Y chromosome define three non-overlapping regions termed AZF (azoospermia factor) which are associated with reduced sperm counts (oligospermia) or the complete absence of spermatozoa in the ejaculate (azoospermia).
How are AZF deletions related to male infertility?
Summary Deletions of specific regions on the Y chromosome cause male infertility. Microdeletions of the long arm of the human Y chromosome define three non-overlapping regions termed AZF (azoospermia factor) which are associated with reduced sperm counts (oligospermia) or the complete absence of spermatozoa in the ejaculate (azoospermia).
Which is the most common type of Y chromosome deletion?
The most common types of deletion are AZFc deletions, which are located in the distal portion of Yq, and account for more than 80% of all reported types of Y microdeletions. The human Y chromosome and male infertility.
How are AZFc deletions transmitted from father to son?
Natural transmission of AZFc deletions from fathers to sons has been reported in some instances; however, most men with such deletions require in-vitro fertilisation treatment to overcome their infertility.