...

 

tel +30 210 41 82 681
 





Infertility

Approximately 15% of couples attempting their first pregnancy meet with failure. If no conception takes place naturally following a year of unprotected sex, these couples are classed as infertile. It is estimated that in at least 30% of those cases, the pathology lies with the male partner, while in approx. 20% of cases there may be a problem with both the male and female partners. There are many causes of infertility - a large proportion of them non-genetic (the exact % is difficult to estimate). At Genomedica, we offer a number of tests to establish whether there is a genetic basis to the infertility problem in either partner. 

Our tests include:
  • G-banded karyotype for both men and women
  • Thrombophilia screen for women
  • Y microdeletion screen and
  • CFTR mutation screen for men.
For all of the above tests we require a peripheral blood sample (5-10 ml of peripheral blood in lithium heparin AND EDTA).

1. G-banded karyotype: The G-banded karyotype looks at all 46 chromosomes of the genome. While in many cases, infertility does not have a chromosomal cause, there are cases where an abnormal karyotype is directly linked to infertility.

Examples include:
  • 45,X Turner syndrome and mosaic Turner syndrome (45,X/46,XX) in females.
  • 47,XXX triple X syndrome or mosaic triple X syndrome in females (47,XXX/46,XX)
  • 46,XXY Klinefelter  syndrome in males

kariotipos1


Μale karyotype with an additional chromosome X – 47,XXY Klinefelter syndrome. One of the clinical features of this  
 
syndrome is infertility.
 


Translocation carriers: occasionally 2 chromosomes break and form a reciprocal exchange of the two parts. Translocation carriers have a higher risk of infertility because of the particular way that the chromosomes involved in the translocation behave at meiosis. Τhey also have a higher risk of experiencing recurrent miscarriages.

Robertsonian translocation carriers : a Robertsonian translocation is a specialized translocation between 2 acrocentric chromosomes. In humans, these are chromosome pairs 13, 14, 15, 21 and 22. The Robertsonian translocation der(13;14) is the most common translocation known in man. Carriers, especially male carriers, of Robertsonian translocations experience up to 10-fold higher infertility rates than non-carriers.

2. Thrombophilia screen:
in recent years, a putative link has been reported between unexplained infertility and recurrent implantation failure and thrombophilia gene mutations. Inherited thrombophilia is believed to be a multiple gene disease with more than one defect, which explains why some women with thrombophilia never have a thrombotic event while others have complications. The molecular screen, therefore, can only give an indication as to whether there is a predisposition to thrombophilia, and should be interpreted alongside other factors that contribute to infertility.

The basic screen includes: Factor V Leiden (G169A, R506Q), Prothrombin factor II (G20210Α), MTHFR (C667T), glycoprotein GPIa/IIa, PAI-1 Serpin E1. The extended screen includes a further 8 genes: Factor V R2 haplotype – H1299R, MTHFR (A1298C), Factor XIII V24L, Apo B R3500Q (apolipoprotein B), Apo E (apolipoprotein E), fibrinogen beta chain (FGB), human platelet antigen (HPA1) and angiotensin-converting enzyme (ACE).


3. Y microdeletion screen:


Y chromosome microdeletions are responsible for azoospermia or severe mikroelipsisoligospermia in 10-15% of males.

Most of these deletions involve the Azoospermia factor (AZF) region that is reponsible for normal spermatogenesis. The test involves molecular screening of the ΑΖFa, b and c regions.

 

 

 

 

 

4. Cystic fibrosis screening:  men with a mild, often undiagnosed, form of cystic fibrosis sometimes exhibit congenital bilateral absence of the vas deferens (= the tube that connects the testes to the ejaculatory ducts of the penis). Because sperm is produced normally, but obviously not carried to the penis, these men are not sterile and there are other artificial methods of extracting sperm. We screen male patients for CF carrier status (75% of the most common mutations).

 
   
GreekEnglish (United Kingdom)

 

facebook, FACEBOOK  

 

 

Hosting & Design by MEDICAL PROMOTION

WCAG 2.0 (Level AA)