Y
micro deletions ::Do you believe
if I say that husband couples suffering RPL 32.5% of , husband were carriers of chromosome Y micro deletions and after excluding the female
factor in 13. 5% of the cases.: Do U honestly believe that
there is a link between RPL and male
carriers of Y
chromosome deletions
?? What is your view??
Male Carriers of Chromosome Y Micro deletions
Severe male infertility: Can it be due to micro deletions of the chromosome of long arm of Y
arm?? Ans: Yes. It is quite
possible. Microdeletion of Y arm of a male are the most frequent abnormal molecular genetics of severe male infertility. Such are mainly exhibited by the presence of severe oligozoospermia and non obstructive azoospermia. Nowadays these genetic alterations should be screened
as routine which is important , since they are present in approximately in 9% of the oligo azoospermia males(OAT) .
What are the
different regions of AZF(Azoospermia Factor)
? Ans: At the molecular level
Y chromosome microdeletions affect at least three regions known as azoospermia factor AZFa,b,and C regions
. All these
three regions of Y chromosome are important in sperm production. Therefore to summarize
these three regions are essential for a
successful spermatogenesis. Different
micro deletions have deleterious effects in different aspects of male fertility . It is of note
though the AFZ cv 2/64 deletions since men carrying them produce a higher percentage of nullisomy for the sex chromosome
and NY disomy .
There is a
link between male carriers of Y chromosome
deletions and RPL
. It has been observed that in couples
with RPL a significant
percentage of the males
had chromosome Y micro deletions
. Another study carried out by Agarwal et al in 2015 stated that in couples suffering RPL 32.5%
of males partner were carriers of chromosome Y
micro deletions and after
excluding the female factor
in 13. 5% of the cases.
Interestingly the most frequent micro deletion was the AZFc The incidence
of chromosome Y micro deletion is different in different population
since is linked to
chromosome Y haplogroups
.But another study carried out at Delhi by Venkatesh et al did not
detect any micro deletion in a population of RPL in New Delhi.
Nevertheless
taking in account the population that we are
working with this novel data suggests
that micro deletions in chromosome Y
could be the cause of RPL
so the study of these chromosomal
abnormalities could be offered
to couples with idiopathic abortion .
De novo Duplications / Deletions from Couples with
Normal Karyotype at oogenesis /
spermiogenesis : Yes ,it is possible.
Ans and Reasons: Sporadic early
pregnancy loss occurs in
10-15% clinically recognized gestations. As we have
mentioned earlier must of the cases of miscarriages are due to full chromosomal trisomies
or monosomies. Nevertheless in
some cases the cause of these abortions could be submicroscopic (which can’t be picked up by
traditional karyotyping) chromosomal
changes like duplications and /
or deletions . The problems is that these structural
abnormalities could appear de novo. These mens that even though become parents have a perfectly normal karyotype the
embryos could carry a small duplication or deletion AS such in these cases the recurrence risk would be
similar to general population
With the introduction by pre implantations genetic testing
for aneuploidies for aneuploidy
screening also in couples with normal
karyotype small duplication or deletion
have been indentified
in per implantation embryos also. The introduction of more accurate
techniques like array comparative genomic hybridization and Next Generation sequencing enable the
clinicians the possibility of
detecting these small changes in
the embryo before transfer
in IVF couples
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