Abbreviations & Acronyms aFT = analog-based free testosterone AMS = Aging Questionnaire ASA = American Society of Andrology cFT = calculated free testosterone CI = confidence interval CV = coefficient of variation Objectives: To determine testosterone fractions in Japanese men and to compare these values with those of Framingham Heart Study participants. Methods: We enrolled 498 healthy Japanese men. Total testosterone was assayed by liquid chromatography tandem mass spectrometry, sex hormone-binding globulin was assayed by immunoassay and free testosterone was calculated by a laboratory at the Boston Medical Center. Analog-based free testosterone and immunoassay-based total testosterone were determined by immunoassay. We compared mass spectrometry assay-based total testosterone and calculated free testosterone values in the Japanese participants with values in the American Framingham Heart Study third generation cohort. Results: The mean serum mass spectrometry assay-based total testosterone, sex hormone-binding globulin, and calculated free testosterone values were 439.4 ± 167 ng/dL, 65.34 ± 30.61 nmol/L, and 58.75 ± 20.0 pg/mL, respectively. The correlation coefficients with age for mass spectrometry assay-based total testosterone, sex hormone-binding globulin, and calculated free testosterone were 0.0010, 0.5041, and −0.496, respectively. There were no age-related changes in mass spectrometry assay-based total testosterone values in healthy men (P = 0.981), whereas sex hormone-binding globulin and calculated free testosterone levels showed similar age-related changes (P < 0.0001). Serum analog-based free testosterone levels (8.24 ± 2.9 pg/mL) showed age-related changes (P < 0.0001) regardless of immunoassay-based total testosterone levels (P = 0.828). Serum immunoassay-based total testosterone values (486.1 ± 162.5 ng/dL) correlated with serum mass spectrometry assay-based total testosterone values (r = 0.740, 95% confidence interval 0.6965-0.7781, P < 0.0001). Similarly, analog-based free testosterone and calculated free testosterone values showed a highly significant correlation (r = 0.706, 95% confidence interval 0.6587-0.7473, P < 0.0001). The analog-based free testosterone values were approximately 10% of the calculated free testosterone values. Conclusions: In contrast to the Framingham Heart Study cohort, total testosterone values in Japanese men are not associated with advancing age; thus, they cannot be used to diagnose late-onset hypogonadism in Japan. The analog-based free testosterone value can be considered instead as a suitable biochemical determinant for diagnosing late-onset hypogonadism syndrome.

23Purpose: This study was designed to identify the endogenous retroviruses (ERVs ) 24 associated with testis-specific transcripts linked to the Y (TTYs) in the azoospermia 25 factor (AZF)b region. We evaluated the relationship between ERVs, TTY expression 26 patterns, and TTY function in spermatogenesis. 27Material and Methods: Identification of TTY family members in the AZFb region 28 was performed using computational screening. After investigating the relationship 29 between ERV genome and TTY expression patterns. We screened genomic PCR 30 products from TTY13 amplified from 790 individuals: 275 azoospermia patients, 285 31 oligozoospermia patients, and 230 fertile males in Japanese subjects. 32Results: Computational screening revealed three TTY family members (TTY9, 10, and 33 13) regulated by ERVs in the AZFb region. Homologous recombination between LTR 34of a TTY13-associated ERV, HERV-K14C, resulted in TTY13 deletion events. These 35 deletions were more frequent in azoospermic and oligozoospermic patients than in 36 fertile males. Specifically 15.63% of the azoospermia group had only the deletion 37 variant, 10.88% of the oligozoospermia group, and 0% of the fertile controls indicating 38 that there is an association between the rate of homologous recombination and the 39 severity of spermatogenesis failure that shows statistical significances (p<0.05). 40 Conclusions 41３

Abbreviations & AcronymsObjectives: Deletions in the azoospermia factor regions are the most common known molecular genetic cause of human male infertility involving spermatogenetic failure. Testing for these deletions in Japanese DNA samples using conventional sequence-tagged site probes occasionally lead to considerable non-specific or faint products in the Japanese population. The aim of the present study was to evaluate the sensitivity and specificity of a newly developed kit for the detection of azoospermia factor microdeletions in the Japanese population. Methods: Sequence-tagged site probes were reselected and the Luminex suspension array assay was carried out. Validation was retrospectively carried out with 2014 DNA sequences with known microdeletions, which were divided into four categories. Results: Category 1 deletions that corresponded to the conventional classification of azoospermia factor deletion were present in 83 men (4.2%), which can result in intrachromosomal homologous recombination. Kit data confirmed the presence of deletions of this type in DNA sequences known to harbor the azoospermia factor deletions. Category 2 deletions involved cytogenetic abnormalities in 28 men (1.4%), whereas category 3 deletions in 759 men (37.7%) were atypical classifications including the gr/gr deletion. As these deletions are thought to be a result of palindromic units and non-homologous recombination, these microdeletions might impact in the interpretation of some clinical findings. The rest of the 1145 cases (56.8%) were assigned to category 4 as normal variants (polymorphism/no deletion). Conclusions:The present findings show that this new kit offers good sensitivity and specificity with the advantage of saving in terms of cost and time.

Increasing evidence shows a relationship between epigenetic regulation and male infertility. The GTF2A1L gene promoter contains the DNA methylation site of a tissue-specific differentially methylated region (TDMR). Eighty-six patients with non-obstructive azoospermia were assessed for the DNA methylation state of CpG islands in the GTF2A1L promoter using testicular genomic DNA. Based on histological criteria, 26 of the 86 patients had normal spermatogenesis (controls), 17 had hypospermatogenesis and 26 had a Sertoli cell-only phenotype or tubular sclerosis. GTF2A1L TDMR methylation was significantly lower in testes DNA from control samples than from hypospermatogenic samples (P=0.029). Patients with hypospermatogenesis were divided into two subgroups: high DNA methylation (HM, n=5) and low DNA methylation (LM, n=12). The GTF2A1L TDMR methylation rate differed significantly between the HM and LM groups (P=0.0019), and GTF2A1L expression was significantly higher among the LM than in the HM patients (P=0.023). High TDMR methylation was correlated with low GTF2A1L gene expression levels. Both groups demonstrated relatively good outcomes with respect to sperm retrieval, fertilisation, pregnancy and childbirth rates. We observed that aberrant GTF2A1L gene expression was not correlated with fertilisation rates. The testicular sperm extraction (TESE) technique may be used to overcome male infertility due to aberrant TDMR methylation.