Severi Giulia, Ambrosini Enrico, Caramanna Luca, Monti Luigi, Magini Pamela, Innella Giovanni
Medical Genetics Unit, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Bologna, Italy.
Medical Genetics Unit, University Hospital of Parma, Parma, Italy.
J Assist Reprod Genet. 2024 Nov;41(11):3173-3177. doi: 10.1007/s10815-024-03250-2. Epub 2024 Sep 11.
To report an exceptional case of male-to-male transmission of genetically based non-obstructive azoospermia (NOA) and varicocele through a naturally obtained pregnancy.
A father and his son were both diagnosed with NOA after centrifugation and varicocele. The father has no other clinical concerns apart from infertility, detected after many attempts of having another child, but given his urological situation (bilateral varicocele and NOA) assisted reproductive techniques were discouraged. After genetic counseling, several genetic-chromosomal analyses were carried out in the son (karyotype, chromosome Y microdeletions, CFTR screening, NGS infertility panels, and finally array-CGH).
After a series of inconclusive tests, array-CGH detected a deletion of 224-283 kb (del9p24.3) involving part of the KANK1 and DMRT1 genes, inherited from the father. Haploinsufficiency of DMRT1 was therefore considered the determining factor in the development of azoospermia in the family by a loss of function mechanism.
The confirmation of father-to-son transmission of a deletion including DMRT1 represents an important point for clinicians dealing with male infertility, even when complete azoospermia is repetitively detected, and must be of hope for a relevant portion of men. Inclusion criteria for the access to assisted reproductive techniques may also be reconsidered and worthy of a greater number of clinical insights. Finally, since DMRT1 alterations have been associated with NOA and abnormal testicular development, but not specifically with varicocele, further studies are required to validate this issue, as varicocele may have played a crucial role in this case.
报告一例基于基因的非梗阻性无精子症(NOA)和精索静脉曲张通过自然受孕实现男性间遗传传递的特殊病例。
一位父亲及其儿子经离心检查后均被诊断为NOA和精索静脉曲张。除了多次尝试生育后发现的不育问题外,父亲没有其他临床问题,但鉴于其泌尿外科情况(双侧精索静脉曲张和NOA),不建议采用辅助生殖技术。经过遗传咨询后,对儿子进行了多项遗传染色体分析(核型分析、Y染色体微缺失检测、CFTR筛查、新一代测序不育症检测组,最后进行了比较基因组杂交芯片分析)。
经过一系列无定论的检测后,比较基因组杂交芯片分析检测到一个224 - 283 kb的缺失(del9p24.3),涉及部分KANK1和DMRT1基因,该缺失遗传自父亲。因此,通过功能丧失机制,DMRT1单倍体不足被认为是该家族无精子症发生发展的决定性因素。
证实包含DMRT1的缺失可从父亲传给儿子,这对处理男性不育症的临床医生来说是一个重要信息,即使反复检测到完全无精子症,对相当一部分男性来说也带来了希望。辅助生殖技术的准入标准也可能需要重新考虑,值得进行更多的临床研究。最后,由于DMRT1改变与NOA和睾丸发育异常有关,但与精索静脉曲张没有特异性关联,因此需要进一步研究来验证这个问题,因为精索静脉曲张在该病例中可能起到了关键作用。