Genetics and Immunology · Reproductive Genetics
Abstract
We report the case of a 38-year-old man whose diagnostic workup for primary infertility led to the discovery of obstructive azoospermia due to bilateral papillary cystadenoma of the epididymis (PCE). Given the rarity of this finding and because PCE could be a manifestation of Von Hippel-Lindau disease (VHL), although the patient had no family or personal history of VHL, the VHL gene was tested, and a known pathogenetic variant (c.464-1G>A; p.)? was found. Screening for other Von Hippel-Lindau disease-associated neoplasms revealed bilateral retinal capillary hemangioblastomas, clear cell renal cell carcinoma, and multiple pancreatic cysts. In this case, an accurate diagnostic workup for male infertility allowed the detection of a rare life-threatening syndrome, already presenting with several silent neoplasms. For this reason, this case report may be useful for reproductive medicine specialists in the management of male infertility.
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Preimplantation genetic testing for male factor infertility: lights and shadows
Mazzilli R et al., 2026 · Journal of endocrinological investigation
Male factor could contribute, alone or in combination with female factor, to the inability to conceive in a couple in more than half of cases. The effect of male factor infertility (MFI) on embryological assisted reproductive technology (ART) outcomes remains an ongoing discussion. to evaluate the impact of MFI on embryo aneuploidy rates, to better understand the role and possible indication for Preimplantation genetic testing for aneuploidies (PGT-A), considering the role of sperm characteristics, paternal age, sperm DNA fragmentation and sperm aneuploidies. this narrative review included all available articles, published up to January 2026. Available evidence, often based on heterogeneous and old-fashioned methodologies, suggests that MFI may impair embryonic development, particularly in terms of fertilization rate and blastulation rate, more than embryo euploidy; however, a comprehensive evaluation of MFI should be integrated into clinical practice in the context of couple infertility, to also optimize the efficiency and outcomes of ART. Promising results emerged from sperm DNA fragmentation as a tool to predict embryo euploidy, but further investigations involving larger sample sizes and improved standardization are required.
Pathophysiology-Based Classification of Male Infertility: Evidence from an 800-patient Prospective Cohort
Grande G et al., 2026 · The Journal of clinical endocrinology and metabolism · Free to read
Male factor infertility (MFI) is frequently labelled idiopathic when evaluation relies primarily on semen analysis, potentially overlooking endocrine and pathophysiological mechanisms relevant for targeted management. To phenotypically define MFI and develop a pathophysiology-based classification aimed at reducing idiopathic infertility following comprehensive evaluation. Prospective monocentric cohort study conducted at a tertiary referral academic centre. Eight hundred male partners of infertile couples evaluated between October 2024 and January 2026 after exclusion of isolated female factor infertility. Prevalence of MFI categories, hormonal patterns across phenotypes, and proportion of idiopathic infertility after comprehensive work-up. All patients underwent standardized clinical evaluation, hormonal assessment (total testosterone, FSH, LH), testicular ultrasound, and complete semen analysis. Microbiological testing, transrectal ultrasound, and genetic analyses were performed according to guidelines. Primary spermatogenic failure was the most prevalent category (56.0%), followed by infection/inflammation (22.4%) and hypogonadotropic hypogonadism (8.5%). Idiopathic infertility was identified in only 5.3% of cases. Distinct endocrine profiles were observed, with high-FSH spermatogenic failure representing the dominant phenotype. Comprehensive phenotyping markedly reduces the proportion of patients classified as having idiopathic infertility and identifies clinically relevant subgroups. This prospective study provides validation of a pathophysiology-based classification and supports a shift toward endocrine-integrated diagnostic strategies in male infertility, with potential implications for targeted management.
Neoplastic Risk in Patients With Klinefelter Syndrome
Graziani A et al., 2026 · Andrology · Free to read
Besides gonadal involvement (hypogonadism, male factor infertility, and testicular hypotrophy), patients with Klinefelter syndrome (KS) may suffer from several extra-gonadic complications, including neoplastic events. The aim of this review is to summarize all major clinical evidence dealing with the association between KS and neoplastic diseases and provide practical suggestions for the management of patients with KS regarding neoplastic risk. This narrative review was conducted through a comprehensive search of the PubMed database, using combinations of the following keywords: "Klinefelter syndrome," "cancer," "neoplasm," "breast cancer," "germ cell tumor," "lymphoma," and "testosterone replacement therapy". KS is associated with a higher risk of breast cancer and mediastinal germ cell tumors and an apparent higher risk of hematological malignancies, in particular non-Hodgkin lymphoma and leukemia. Evidence on testicular cancer is limited, with no clear increase in risk attributable to KS, while prostate cancer has a lower risk and lower mortality rate. Given the complexity of the syndrome and the limited available evidence, regular clinical follow-up with targeted investigations when clinically indicated may facilitate early diagnosis and management of associated comorbidities.
Impact of reference gender on bone mineral density and fracture risk assessment in transgender adults
Scala A et al., 2026 · Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA · Free full text on PubMed Central
In transgender adults, reference-gender choice alters Z-scores and fracture-risk estimates. Z-scores differ by 0.4-0.6 SD, with male references identifying more individuals with low BMD for age, especially in those assigned male at birth. Dual-reference reporting is advisable until further evidence becomes available. Transgender individuals, especially those assigned male at birth (AMAB), exhibit lower bone mineral density (BMD) compared with the cisgender population. Interpretation of densitometric data is challenging, as the choice of reference gender can significantly influence Z-scores and fracture risk scores. This study aims to evaluate the impact of the gender reference database (male or female) on the assessment of BMD and fracture risk in transgender adults prior to gender-affirming hormone therapy (GAHT). We conducted a cross-sectional analysis of 249 transgender individuals (153 assigned female at birth - AFAB and 96 AMAB) aged 18-43 years, recruited in the Hospitals of Padua and Brescia (Italy). Z-scores were calculated using both male and female reference databases and FRAX scores were computed using both gender inputs. Associations with anthropometric, biochemical, and hormonal parameters were explored. Z-scores differed systematically depending on the reference gender, with mean ΔZ ranging 0.4-0.6 SD across skeletal sites. Switching reference databases frequently led to reclassification of BMD status. AMAB individuals showed a higher prevalence of low BMD for age, particularly when assessed against male references (27.1%), whereas AFAB participants generally maintained normal BMD. However, FRAX scores remained low. BMI and 25-OH vitamin D levels were independent predictors of BMD and Z-scores in AMAB individuals. The choice of reference gender significantly influences densitometric interpretation in young transgender adults. Until further evidence becomes available, calculating Z-scores using both male and female reference databases is advisable. Early preventive interventions remain essential to preserve bone health.
Related research
Human male infertility and Y chromosome deletions: role of the AZF-candidate genes DAZ, RBM and DFFRY
Ferlin A et al., 1999 · Human reproduction (Oxford, England)
Microdeletions in Yq11 overlapping three distinct 'azoospermia factors' (AZFa-c) represent the aetiological factor of 10-15% of idiopathic azoospermia and severe oligozoospermia, with higher prevalence in more severe testiculopathies, such as Sertoli cell-only syndrome. Using a PCR-based screening, we analysed Yq microdeletions in 180 infertile patients affected by idiopathic Sertoli cell-only syndrome and different degrees of hypospermatogenesis, compared with 50 patients with known causes of testicular alteration, 30 with obstructive azoospermia, and 100 normal fertile men. In idiopathic severe testiculopathies (Sertoli cell-only syndrome and severe hypospermatogenesis), a high prevalence of microdeletions (34.5% and 24.7% respectively) was found, while milder forms were not associated with Yq alteration. No deletions were found in testiculopathies of known aetiology, obstructive azoospermia, normal fertile men and male relatives of patients with deletions. Deletions in the AZFc region involving the DAZ gene were the most frequent finding and they were more often observed in severe hypospermatogenesis than in Sertoli cell-only syndrome, suggesting that deletions of this region are not sufficient to cause complete loss of the spermatogenic line. Deletions in AZFb involving the RBM gene were less frequently detected and there was no correlation with testicular phenotype, with an apparent minor role for such gene in spermatogenesis. The DFFRY gene was absent in a fraction of patients, making it a candidate AZFa gene. Our data suggest that larger deletions involving more than one AZF-candidate gene are associated with a more severe testicular phenotype.
Absence of testicular DAZ gene expression in idiopathic severe testiculopathies
Ferlin A et al., 1999 · Human reproduction (Oxford, England)
Deletions of the DAZ (deleted in azoospermia) gene family are frequently responsible for male infertility and are generally assessed by analyses of genomic DNA extracted from peripheral leukocytes. The multicopy nature of this gene prevents the distinction of intragenic deletions or deletions not involving the whole DAZ gene cluster. Thus it is still unclear whether each DAZ copy is effectively expressed in the testis. We analysed, by reverse transcription-polymerase chain reaction (RT-PCR), the expression of DAZ, RBM and SRY genes, in testicular cells from infertile men affected by idiopathic severe hypospermatogenesis, obstructive azoospermia and Sertoli cell-only syndrome. Normal mRNA for DAZ, RBM and SRY were observed in obstructive azoospermia, whereas only SRY transcripts were detected when only Sertoli cells were present. Nine out of 10 patients affected by idiopathic severe hypospermatogenesis had normal expression of SRY, RBM and DAZ, while in one patient no DAZ transcript was detected, suggesting that his testiculopathy was related to the absence of DAZ expression. The lack of DAZ mRNA in testicular cells with an apparently normal DAZ gene constitution on DNA extracted from leukocytes may be explained by different hypotheses: (i) not all the copies of the DAZ gene cluster are transcribed in the germ cells and the reported patient had a small deletion involving only the active ones; (ii) the patient may be mosaic for the DAZ gene having a normal constitution in leukocytes and be deleted for DAZ gene in the testis; (iii) abnormalities of DAZ transcription may exist. These findings highlight the intrinsic interpretative difficulties of normal PCR analysis for DAZ and RBM on leukocytes and suggest caution in the use of germ cells for assisted reproductive techniques in these cases to avoid transmission of genetic abnormalities to male offspring.
Analysis of the DAZ gene family in cryptorchidism and idiopathic male infertility
Ferlin A et al., 2004 · Fertility and sterility
To investigate whether partial deletions of the DAZ gene family on the Y chromosome are associated with cryptorchidism, similar to that found for complete AZF deletions. Prospective study. University hospital. PATIENT(S): A total of 193 azoospermic and severely oligozoospermic men: 95 with a history of cryptorchidism and 98 classified as idiopathic. INTERVENTION(S): A two-part study for Y chromosome microdeletions was performed: a polymerase chain reaction (PCR)-based analysis for complete AZF deletions and partial DAZ gene analysis by PCR-restriction digestion assay for single-family variants. MAIN OUTCOME MEASURE(S): Presence and type of AZF deletions and number of DAZ genes present. RESULT(S): The frequency of complete AZF deletions was similar in idiopathic (13.3%) and cryptorchid men (11.6%), but partial DAZ deletions were found only in infertile subjects without cryptorchidism (7.1%). The testicular phenotype was similar in men with complete AZF deletions and partial DAZ deletions, therefore the contribution of the other AZF genes in determining the spermatogenic impairment is still unclear. CONCLUSION(S): Our findings suggest that the loss of only some copies of DAZ is sufficient to lead to severe male infertility, but it is not a frequent finding in cryptorchid men.
Mutations in dynein genes in patients affected by isolated non-syndromic asthenozoospermia
Zuccarello D et al., 2008 · Human reproduction (Oxford, England)
Asthenozoospermia (AZS) is a common cause of male infertility characterized by reduced forward motility (WHO grade A+B sperm motility <50% or A < 25%) or absent sperm motility in fresh ejaculate. AZS may exist as an isolated disorder, in combination with other sperm anomalies or as part of a syndromic association. Up to date, only a few genes, constituting the cilia/flagella structure, have been associated with isolated AZS in humans, whereas several other genes are known to be involved in syndromic form of AZS, including primary ciliary dyskinesia (PCD) and Kartagener syndrome (KS). Axonemal ultrastructural defects, including absent or shortened arms of dyneins, can be found in >50% of PCD/KS patients. Approximately 90% of KS male patients are affected by AZS. The majority of KS patients can be ascribed to dynein genes mutations. Mutation screening of DNAI1, DNAH5 and DNAH11 genes was performed in 90 patients with isolated non-syndromic AZS and 200 controls. We found three mutations (one in each gene) specifically associated with AZS in seven patients (7.8%). Mutations are inherited from the mothers and may be found in familial clusters. No ultrastructural axonemal anomaly was detected in sperm. We report for the first time a possible association between mutations in dynein genes and isolated AZS. Male carriers of the mutations always exhibit AZS, whereas female carriers manifest no alterations in either fertility or pulmonary clearance.