Whole genome sequencing of children born after fertilization with ICSI using testicular sperm

Azoospermia is one of the most severe forms of male infertility, no sperm is
found in the ejaculate. Azoospermia is observed in about 5-10% of infertile
couples, the origin is a spermatogenetic abnormality where sperm maturation and
production is affected. In about half of the males with azoospermia, sperm can
be found in the testis. By taking a testicular biopsy (testicular sperm
extraction, TESE), sperm can be found and isolated to be used for
intracytoplasmic sperm injection (ICSI). After fertilization of the oocytes
with this testicular sperm, the best embryo*s (maximally 2) are transferred to
the female partner (fresh embryo transfer, ET) or embryo's are cryopreserved
for a later transfer (cryo- ET). The pregnancy rates with TESE-ICSI embryo*s
are comparable to the pregnancy rates with standard IVF procedures using
ejaculated sperm.
ICSI-TESE has been introduced in 1993 (Brussels) and is the treatment of choice
for male fertility treatment in case of non-obstructive azoospermia. In the
Netherlands, TESE was not allowed until 2007, when the CCMO allowed it again
under a strict research protocol (NL12408.000.06). The available literature
concerning the follow up of the children born from TESE-ICSI indicates that the
risk of genetic anomalies or congenital malformations does not differ from
children born after ICSI or IVF with ejaculated sperm. In our own data
including ICSI children and PESA-ICSI children (from epididymal sperm), we
found no differences between both groups (see doctoral thesis dr. G. Woldringh,
and Woldringh G.H., Hum Reprod Update 2010;16(1):12-9, Woldringh G.H., Hum
Reprod 2011;26(7):1759-67). In a pilot study carried out by the same
researcher, a higher number of *de novo copy number changes* (CNV) were found
in the PESA-ICSI- children, however no characteristic fenotype could be
attributed to them, concluding that changes found in the genome do not always
have a (directly visible) clinical translation (Woldringh G.H. Hum Reprod
2009;24,233-240). With the recent introduction of Next Generation sequencing, a
powerful tool for clinical research into (un)known (pathological) mutations, at
the department of Human Genetics of the Radboud University Nijmegen Medical
Centre. It is now possible to test the complete human exome in just one test.
Taking into account the limited data available about the risk of introducing de
novo mutations in TESE-children, we want to start this pilot project in order
to estimate the probability of increasing DNA mutations in the offspring of
non-obstructive azoospermic males.

In this pilot study we intent to evaluate whether children born from TESE-ICSI
treatment are at risk for increased de novo (pathological) mutations. This
research is novel and pioneering, and never published before. We expect the
outcome to be important for the use of this fertility treatment worldwide,
independent of the outcome (either reassuring or not)

Observational study into the existence of de novo mutations in TESE-ICSI
children born from a non-obstructive azoospermic father.

The burden or risk for the probands in this study (children and parents) is
considered minimal. Patients will undergo a vena puncture once (at the local
hospital/ family doctor or at the department of Human Genetics). The reason why
children are involved in this study is that the TESE-ICSI technique has been
re-introduced in the Netherlands since 2007, therefore the oldest children born
from this treatment are not older than 4-5 years.