Biological and Clinical Significance of Mosaicism in Human Preimplantation Embryos.

Applications and indications of assisted reproduction technology are expanding, but every new approach is under scrutiny and thorough consideration. Recently, groups of assisted reproduction experts have presented data that support the clinical use of mosaic preimplantation embryos at the blastocyst stage, previously excluded from transfer. In the light of published contemporary studies, with or without clinical outcomes, there is growing evidence that mosaic embryos have the capacity for further in utero development and live birth. Our in-depth discussion will enable readers to better comprehend current developments. This expansion into the spectrum of ART practices requires further evidence and further theoretical documentation, basic research, and ethical support. Therefore, if strict criteria for selecting competent mosaic preimplantation embryos for further transfer, implantation, fetal growth, and healthy birth are applied, fewer embryos will be excluded, and more live births will be achieved. Our review aims to discuss the recent literature on the transfer of mosaic preimplantation embryos. It also highlights controversies as far as the clinical utilization of preimplantation embryos concerns. Finally, it provides the appropriate background to elucidate and highlight cellular and genetic aspects of this novel direction.

TCF7L2 gene variants predispose to the development of type 2 diabetes mellitus among individuals with metabolic syndrome.

INTRODUCTION: Transcription factor 7-like 2 (TCF7L2) gene variants rs12255372 and rs7903146 have been consistently shown to raise genetic risk for type 2 diabetes mellitus (T2DM). The aim of this study was to investigate the possible role of these variants in the development of impaired glucose metabolism (IGM), including impaired fasting glucose (IFG) or T2DM, in patients with metabolic syndrome (MS). PATIENTS AND METHODS: The study population consisted of 228 patients with MS who were divided into two groups. The first group consisted of 148 patients with MS and IGM [39M/109F, 59.8 ± 14.6 (mean ± SD) years] and the second group of 80 patients with MS and normoglycemia (NGM) (16M/64F, 56.1 ± 15.8 years). The diagnosis of MS was based on the criteria proposed by the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) Scientific Statement. Anthropometric parameters including BMI and waist circumference were recorded and blood samples were obtained after overnight fasting for biochemical tests. The rs12255372 and rs7903146 TCF7L2 polymorphisms were genotyped in peripheral blood leucocytes. RESULTS: Analysis of the distribution of the TCF7L2 polymorphic alleles revealed that the frequency of the T allele of the TCF7L2 variant rs12255372 was 38.2% in the study population, while the frequency of the T allele of the TCF7L2 rs7903146 variant was 35.3%. The T allele of the rs12255372 variant was more frequently present in patients with MS and IGM (48.3%) compared to patients with MS and NGM (19.4%, p < 0.001). Also, the T allele of rs7903146 was more frequently present in patients with MS and IGM (44.6%) compared to patients with MS and NGM (18.1%, p < 0.001). Logistic regression analysis followed and revealed that the presence of the T allele for both rs12255372 and rs7903146 TCF7L2 gene variants is a very powerful predictor of the presence of glucose disorders, increasing the risk more than fourfold in patients with MS and after adjustment for potential confounders, such as age, gender, BMI, and waist circumference (TCF7L2 rs12255372: Exp(B) 4.917, p < 0.001 and TCF7L2 rs7903146: Exp(B) 5.460, p < 0.001). CONCLUSION: The presence of the rs12255372 and rs7903146 TCF7L2 gene variants plays an important role in the development of T2DM among individuals with MS. These findings support the notion that among subjects with MS, those who finally develop T2DM have a genetic predisposition to ß-cell dysfunction.

Rare Association of Hb D-Los Angeles (HBB: c.364G>C) with Hb H Disease: Diagnosis and Clinical Implications.

Hb D-Los Angeles (or Hb D-Punjab) (HBB: c.364G > C) is found worldwide and is derived from a point mutation in the ß-globin gene prevalent in the Punjab region of Northwestern India. Heterozygous or homozygous inheritance does not cause significant medical problems, whereas association with other hemoglobinopathies, especially ß-thalassemia (ß-thal) and sickle cell disease, changes the phenotype. Coinheritance of Hb D-Los Angeles with Hb H disease (α-/- -) has never been reported before. The presence of this rare combination in a family of Greek origin is herein described, and the challenges involving clinical management are discussed.

Retrotransposon expression and incorporation of cloned human and mouse retroelements in human spermatozoa.

OBJECTIVE: To investigate the expression of long interspersed element (LINE) 1, human endogenous retrovirus (HERV) K10, and short interspersed element-VNTR-Alu element (SVA) retrotransposons in ejaculated human spermatozoa by means of reverse-transcription (RT) polymerase chain reaction (PCR) analysis as well as the potential incorporation of cloned human and mouse active retroelements in human sperm cell genome. DESIGN: Laboratory study. SETTING: University research laboratories and academic hospital. PATIENT(S): Normozoospermic and oligozoospermic white men. INTERVENTION(S): RT-PCR analysis was performed to confirm the retrotransposon expression in human spermatozoa. Exogenous retroelements were tagged with a plasmid containing a green fluorescence (EGFP) retrotransposition cassette, and the de novo retrotransposition events were tested with the use of PCR, fluorescence-activated cell sorting analysis, and confocal microscopy. MAIN OUTCOME MEASURE(S): Retroelement expression in human spermatozoa, incorporation of cloned human and mouse active retroelements in human sperm genome, and de novo retrotransposition events in human spermatozoa. RESULT(S): RT-PCR products of expressed human LINE-1, HERV-K10, and SVA retrotransposons were observed in ejaculated human sperm samples. The incubation of human spermatozoa with either retrotransposition-active human LINE-1 and HERV-K10 or mouse reverse transcriptase-deficient VL30 retrotransposons tagged with an EGFP-based retrotransposition cassette led to EGFP-positive spermatozo; 16.67% of the samples were positive for retrotransposition. The respective retrotransposition frequencies for the LINE-1, HERV-K10, and VL30 retrotransposons in the positive samples were 0.34 ± 0.13%, 0.37 ± 0.17%, and 0.30 ± 0.14% per sample of 10,000 spermatozoa. CONCLUSION(S): Our results show that: 1) LINE-1, HERV-K10, and SVA retrotransposons are transcriptionally expressed in human spermatozoa; 2) cloned active retroelements of human and mammalian origin can be incorporated in human sperm genome; 3) active reverse transcriptases exist in human spermatozoa; and 4) de novo retrotransposition events occur in human spermatozoa.

The ovarian response to standard gonadotropin stimulation is influenced by AMHRII genotypes.

The aim of the current study was to explore whether anti-Müllerian hormone receptor II (AMHRII) genetic variants influence the hormonal profile and the ovarian response to standard gonadotropin stimulation of women undergoing medically assisted reproduction. Three hundred in vitro fertilization or intracytoplasmic sperm injection patients constituted the study population, while 300 women with at least one spontaneous pregnancy participated as controls. The follicle-stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2) and AMH levels were determined at the third day of the menstrual cycle. AMHRII 10A > G (rs11170555), 1749C > T (rs2071558) and -482A > G (rs2002555) polymorphisms were genotyped. The follicle and oocyte numbers, the follicle size and the clinical pregnancies were recorded. Regarding the AMHRII 1749C > T polymorphism, 1749CT women presented with higher total follicle and small follicle numbers compared to 1749CC women (p = 0.04 and p = 0.01, respectively). Whereas, as concerns the -482A > G polymorphism, -482AG women were characterized by higher total follicle and small follicle numbers comparing with -482AA women (p = 0.07 and p = 0.004, respectively). Finally, -482AG women presented with increased FSH levels compared to -482AA women (p < 0.05). However, no associations of AMHRII gene polymorphisms with serum AMH levels or clinical pregnancy rates were observed. AMHRII 1749C > T and -482A > G genetic variants were associated with the ovarian response to standard gonadotropin stimulation, affecting mainly the follicular growth.

Ovarian hyperstimulation syndrome inhibition by targeting VEGF, COX-2 and calcium pathways: a preclinical randomized study.

OBJECTIVE: The efficacy of vascular endothelial growth factor (VEGF), COX-2, calcium and aromatase inhibitors in an ovarian hyperstimulation syndrome (OHSS) rat model was tested. METHODS: One hundred and eight female Wistar rats were randomly divided in nine groups. The control group received saline, while the OHSS group received rec-FSH for 4 consecutive days. The other seven groups received rec-FSH (4d) and Bevacizumab twice, Parecoxib daily, Verapamil daily, Parecoxib daily and Bevacizumab twice, Verapamil daily and Bevacizumab twice, Parecoxib and Verapamil daily, Letrozole and Meloxicam daily, respectively. All groups received also hCG at the 5th day. RESULTS: All intervention groups were characterized by reduced vascular permeability compared to the OHSS group, which in the groups of Verapamil (Calcium inhibition) and Parecoxib + Verapamil (COX-2 + Calcium inhibition) presented significant statistical difference. The Verapamil group showed the lowest corpus luteum formation, while the Parecoxib (COX-2 inhibition), the Parecoxib + Verapamil (COX-2 + Calcium inhibition), the Bevacizumab + Parecoxib (VEGF + COX-2 inhibition) and the Bevacizumab + Verapamil (VEGF + Calcium inhibition) groups were also characterized by lower corpus luteum numbers compared to the OHSS group. Furthermore, lower graafian follicle formation was observed in the above groups, while the ovarian weight and the hormonal profile were not significantly affected. CONCLUSIONS: Studying the different check points of the VEGF pathway, we conclude that targeting calcium pathways could be beneficial for the vascular permeability control in an OHSS animal model.

The follicular outcome after standard gonadotropin stimulation is associated with ERα and ERß genotypes.

The aim is to study the association of estrogen receptor α (ERα) and estrogen receptor ß (ERß) gene polymorphisms and diplotypes with ovarian response to follicle-stimulating hormone (FSH) stimulation and the hormone levels [FSH, luteinizing hormone (LH), E2] at the third day of the menstrual cycle. Three hundred women undergoing medically assisted reproduction and 300 women with at least one spontaneous pregnancy participated in the study. ERα PvuII and XbaI polymorphisms as well as ERß AluI polymorphism were genotyped. The FSH, LH, and E2 levels were determined at the third day of the menstrual cycle, while the follicular size, the follicle, and oocyte numbers were recorded during oocyte retrieval. PvuII CC, XbaI GG, and AluI GG women were characterized by increased amounts of large follicles compared to PvuII TT, XbaI AA, and AluI AA women (p = 0.045, 0.01, and 0.033, respectively). The PvuII CC/XbaI GG diplotype was also significantly associated with higher large follicle numbers compared to the PvuII TT/XbaI AA diplotype (p = 0.024). However, no associations were observed between ER gene polymorphisms and the hormonal profile, the follicle/oocyte numbers, and the pregnancy rates. ERα and ERß genetic variants were associated with ovarian response to standard gonadotropin stimulation of women undergoing in-vitro fertilization affecting mainly the follicular growth.

Association of the (TAAAA)n repeat polymorphism of SHBG gene with the age at menopause in Greek postmenopausal women.

OBJECTIVE: To assess the potential association of the pentanucleotide (TAAAA)n repeat polymorphism in the promoter of SHBG gene with the age at menopause in a Greek female population. STUDY DESIGN: Cross-sectional study. Two hundred and ten postmenopausal women aged 46-63 years were enrolled. The age at the last menstrual period and anthropometric parameters were recorded in all participants. Blood sampling for genotyping of the (TAAAA)n polymorphism of SHBG gene was performed. MAIN OUTCOME MEASURE(S): Frequency and association of the (TAAAA)n alleles with age at menopause. RESULTS: The alleles with seven and eight TAAAA repeats were associated with the age at menopause. The age at menopause was higher in carriers than in non-carriers of the (TAAAA)7 allele (50.2±3.1 years vs. 48.0±4.8 years, p=0.026). Furthermore, the age at menopause was lower in women carrying the (TAAAA)8 allele (47.5±4.8 years) than in women not carrying this allele (48.8±4.4 years, p=0.048). CONCLUSIONS: The (TAAAA)7 and (TAAAA)8 alleles of the SHBG (TAAAA)n polymorphism may contribute to variation in the timing of natural menopause in postmenopausal women of Northwestern Greece.

Influence of FSHR diplotypes on ovarian response to standard gonadotropin stimulation for IVF/ICSI.

OBJECTIVE: To explore the association of FSHR 307 (T/A)/FSHR 680(N/S) diplotypes with ovarian response to follicle stimulating hormone (FSH) stimulation of women undergoing medically assisted reproduction (in vitro fertilization [IVF] or intracytoplasmic sperm injection [ICSI]). STUDY DESIGN: The study population consisted of 304 women undergoing IVF/ICSI and 300 women with at least 1 spontaneous pregnancy as controls. FSHR polymorphisms were genotyped. Controlled ovarian stimulation and IVF/ICSI were performed in the 304 couples. During oocyte retrieval the follicular size, the follicle and oocyte numbers were recorded. Serum FSH, luteinizing hormone and estradiol were determined at the third day of the menstrual cycle. RESULTS: The FSHR 307(T/A)/FSHR 680(N/S) diplotype analysis revealed lower serum FSH levels, higher follicle and oocyte numbers, increased numbers of large follicles as well as decreased empty follicle numbers in Thr307Thr/Asn680Asn women as compared to Thr307 Ala/Asn680Ser and Ala307Ala/Ser680Ser women (p < 0.006, p < 0.01, p < 0.008, p < 0.01, p < 0.005, respectively). CONCLUSION: FSHR diplotypes were significantly associated with ovarian response to gonadotropin stimulation. FSHR diplotype analysis could be informative for ovarian stimulation outcome and the selection of the proper stimulation protocol, which would ensure a sufficient number of mature oocytes for IVF/ICSI.

Sperm flow cytometric parameters are associated with ICSI outcome.

The association of sperm nuclear chromatin condensation and ploidy with embryo development and outcome after intracytoplasmic sperm injection (ICSI) was explored. The study population consisted of 16 couples referred to Ioannina University Medical School In vitro Fertilization Unit with male factor infertility and serious impairments in sperm nuclear chromatin condensation and ploidy, according to sperm flow cytometry. Additionally, 20 couples with male factor infertility and relatively high sperm flow cytometry parameters participated as controls. The 35 cycles of the study population were characterized by a lower fertilization rate (P<0.001) as well as decreased grade A embryo rate (P=0.004) and increased grade C embryo rate (P=0.028), compared with the 29 cycles of the control group. Additionally, a significantly elevated arrested embryo rate (P<0.001) and a decreased clinical pregnancy rate (P<0.020) were observed in the couples of the study population. Consequently, high levels of sperm nuclear chromatin condensation abnormalities and sperm aneuploidies are probably associated with lower fertilization rates, impaired embryo quality, elevated arrested embryo rates and decreased pregnancy rates. These preliminary results strongly support the use of sperm flow cytometry as a potential prognostic tool of ICSI outcome.

CYP19 gene variants affect the assisted reproduction outcome of women with polycystic ovary syndrome.

OBJECTIVE: Cytochrome P450 aromatase catalyzes the irreversible transformation of androgens into estrogens. The association of CYP19(TTTA)n polymorphism with the hormonal profile and the assisted reproduction outcome of women with polycystic ovary syndrome (PCOS) was explored. METHODS: One hundred and thirty-two women with PCOS and 200 with male-factor infertility, as controls, participated in the current study. The CYP19(TTTA)n polymorphism was genotyped, while the hormonal profile was determined at the third day of the menstrual cycle. During oocyte retrieval, the follicular size, the follicle and oocyte numbers were recorded. RESULTS: Genotype analysis revealed 6 CYP19(TTTA)n alleles with 7-12 repeats. In PCOS women, the CYP19(TTTA)7 allele presence was associated with lower serum E2 levels at the third day of the menstrual cycle (p < 0.009), lower large follicle (p < 0.02) and total oocyte numbers (p = 0.006), but with significantly higher pregnancy rates after assisted reproduction (p < 0.004). CONCLUSIONS: Potential associations of the CYP19(TTTA)7 allele with ovarian response to standard gonadotrophin stimulation and with assisted reproduction outcome were found in PCOS women, probably due to androgen/estrogen ratio alterations.

The ovarian response to standard gonadotrophin stimulation depends on FSHR, SHBG and CYP19 gene synergism.

PURPOSE: Follicle stimulating hormone, sex hormone-binding globulin and cytochrome P450 aromatase play crucial roles in the regulation of mammalian reproduction. The synergistic effect of FSHR 307(T/A)/FSHR 680(N/S), SHBG(TAAAA) ( n ) and CYP19(TTTA) ( n ) genotypes on ovarian response to standard gonadotrophin stimulation of women undergoing medically assisted reproduction (IVF/ICSI) was explored. METHODS: The study population consisted of 300 women under IVF/ICSI treatment and 300 women with at least with at least one successful child birth as controls. The polymorphisms were genotyped while the follicular size, the follicle and oocyte numbers were recorded during oocyte retrieval. RESULTS: The genotype analysis, excluding heterozygotes for each particular polymorphism, revealed eight combined homozygotic FSHR/SHBG/CYP19 genotypes. A gradual reduction in the number of follicles and oocytes from FSHR 307Thr/680Asn allele/long SHBG allele/long CYP19 allele homozygotes to FSHR 307Ala/680Ser allele/short SHBG allele/short CYP19 allele homozygotes was observed (20.36 ± 6.74 vs. 8.05 ± 2.47, p < 0.008 and 13 ± 4.63 vs. 6.1 ± 2.32, p < 0.02, respectively). CONCLUSIONS: FSHR/SHBG/CYP19 combined genotypes are associated with ovarian response to standard gonadotrophin stimulation of women undergoing medically assisted reproduction.

Phosphatidylethanolamine N-methyltransferase and choline dehydrogenase gene polymorphisms are associated with human sperm concentration.

Choline is a crucial factor in the regulation of sperm membrane structure and fluidity, and this nutrient plays an important role in the maturation and fertilizing capacity of spermatozoa. Transcripts of phosphatidylethanolamine N-methyltransferase (PEMT) and choline dehydrogenase (CHDH), two basic enzymes of choline metabolism, have been observed in the human testis, demonstrating their gene expression in this tissue. In the present study, we explored the contribution of the PEMT and CHDH gene variants to sperm parameters. Two hundred oligospermic and 250 normozoospermic men were recruited. DNA was extracted from the spermatozoa, and the PEMT -774G>C and CHDH +432G>T polymorphisms were genotyped. The genotype distribution of the PEMT -774G>C polymorphism did not differ between oligospermic and normozoospermic men. In contrast, in the case of the CHDH +432G>T polymorphism, oligospermic men presented the CHDH 432G/G genotype more frequently than normozoospermic men (62% vs. 42%, P<0.001). The PEMT 774G/G genotype was associated with a higher sperm concentration compared to the PEMT 774G/C and 774C/C genotypes in oligospermic men (12.5 ± 5.6 × 10(6) spermatozoa ml(-1) vs. 8.3 ± 5.2 × 10(6) spermatozoa ml(-1), P<0.002) and normozoospermic men (81.5 ± 55.6 × 10(6) vs. 68.1 ± 44.5 × 10(6) spermatozoa ml(-1), P<0.006). In addition, the CHDH 432G/G genotype was associated with higher sperm concentration compared to CHDH 432G/T and 432T/T genotypes in oligospermic (11.8 ± 5.1 × 10(6) vs. 7.8 ± 5.3 × 10(6) spermatozoa ml(-1), P<0.003) and normozoospermic men (98.6 ± 62.2 × 10(6) vs. 58.8 ± 33.6 × 10(6) spermatozoa ml(-1), P<0.001). In our series, the PEMT -774G>C and CHDH +432G>T polymorphisms were associated with sperm concentration. This finding suggests a possible influence of these genes on sperm quality.

Aromatase (CYP19) gene variants influence ovarian response to standard gonadotrophin stimulation.

PURPOSE: The association of cytochrome P450 aromatase gene CYP19(TTTA) ( n ) polymorphism with ovarian response to FSH stimulation was explored. METHODS: Three hundred women undergoing medically assisted reproduction and 300 women with at least one spontaneous pregnancy participated in the study. CYP19(TTTA) ( n ) polymorphism was genotyped, while serum hormones were determined. During oocyte retrieval, the follicular size, the follicle and oocyte numbers were recorded. RESULTS: Six CYP19(TTTA) ( n ) alleles with 7 to 12 repeats were revealed. Women homozygous for long CYP19(TTTA) ( n ) alleles presented with lower serum FSH levels at the third day of the menstrual cycle (p < 0.001) and higher large follicle numbers (p < 0.01), compared to women homozygous for short CYP19(TTTA) ( n ) alleles. The CYP19(TTTA) ( 7 ) allele was associated with higher serum FSH levels (p < 0.003), with lower total follicle (p < 0.02) and large follicle numbers (p < 0.03), while CYP19(TTTA) ( 7 ) allele-carriers presented more frequently with small follicles than CYP19(TTTA) ( 7 ) allele-non carriers (p < 0.01). CONCLUSIONS: CYP19 genetic variants were associated with ovarian reserve and response to standard gonadotrophin stimulation of women undergoing in vitro fertilization.

Association of TNFα, TNFR1, and TNFR2 polymorphisms with sperm concentration and motility.

Tumor necrosis factor α (TNFα) is a multifunctional cytokine that regulates various cellular processes related to spermatogenesis. Two types of cell receptors, TNFR1 and TNFR2, mediate TNFα activity. In the present study, we sought to explore the association of TNFα -857C→T, TNFR1 36A→G, and TNFR2 676T→G polymorphisms with sperm concentration and motility. Two hundred ninety men were examined during infertility investigation; of those, 170 men were normozoospermic and 120 were oligospermic. Polymerase chain reaction analysis revealed significant differences in genotype distribution of the TNFR1 36A→G polymorphism between normozoospermic and oligospermic men. Men with oligozoospermia presented TNFR1 36A/A genotypes less frequently than normozoospermic men (P < .001). The presence of the TNFR1 36G allele was significantly increased in oligospermic men (P < .001). Furthermore, the presence of the TNFR1 36G allele was associated with lower sperm concentration in normozoospermic men (P < .03) and in the total study population (P < .001), and with lower sperm motility in normozoospermic men (P < .007) and in the total study population (P < .001). No significant associations were found between TNFα -857C→T and TNFR2 676T→G polymorphisms and semen quality. The TNFR1 36A allele is associated with increased sperm concentration and motility in our series, supporting the significance of TNFR1 gene in semen quality.

Association of the A1330V and V667M polymorphisms of LRP5 with bone mineral density in Greek peri- and postmenopausal women.

UNLABELLED: Wnt signaling through low-density lipoprotein receptor-related protein 5 (LRP5) is an important determinant of bone mass regulation. OBJECTIVE: To explore the influence of two LRP5 single nucleotide polymorphisms (SNPs) A1330V and V667M on bone mineral density (BMD) and serum levels of osteoprotegerin (OPG), receptor activator of nuclear factor-κB ligand (RANKL) and bone metabolic markers in a Greek female population. STUDY DESIGN: Two hundred and nine postmenopausal and twelve perimenopausal women aged 40-63 years were enrolled. All participants underwent spinal BMD evaluation. Genotyping of A1330V and V667M polymorphisms was performed by real-time polymerase chain reaction. Levels of OPG, soluble RANKL (sRANKL) and bone metabolic markers were measured. RESULTS: As regards A1330V SNP, women carrying CT/TT genotypes had lower spinal BMD than women with CC (p<0.0001). Regarding V667M SNP, spinal BMD was lower in women with GA/AA than in women with GG genotypes (p<0.0001). These differences remained significant after adjustment for age, years since menopause and body mass index. The A1330V and V667M polymorphisms were in strong linkage disequilibrium. A significant interaction between A1330V and V667M SNPs on spinal BMD was revealed. The haplotype with both risk alleles of the two SNPs (AT) conferred more risk for low BMD than the haplotypes with one risk allele (GT or AC) or the haplotype-reference (GC) (p=0.046, p=0.045, and p=0.010, respectively). No effect was observed on circulating OPG, sRANKL levels and bone metabolic markers. CONCLUSIONS: These findings demonstrate that the A1330V and V667M polymorphisms are associated with low BMD in peri- and postmenopausal Greek women.

Assessment of sperm chromatin condensation and ploidy status using flow cytometry correlates to fertilization, embryo quality and pregnancy following in vitro fertilization.

PURPOSE: Sperm flow cytometry (SFC) was used to evaluate the association of sperm chromatin condensation and ploidy with fertilization, embryo development, pregnancy and abortion rates following IVF. METHODS: Conventional semen analysis was performed in one hundred fifty men, as well as SFC analysis, after acridine orange and propidium iodide staining, for the evaluation of sperm maturity and ploidy respectively. Conventional IVF was performed in all couples. RESULTS: Couples with low percentages of mature spermatozoa presented with lower fertilization rates (p < 0.005), lower rates of grade A embryos (p < 0.003) and lower pregnancy rates (p < 0.006), compared to couples with high percentages of mature spermatozoa. Couples with low total aneuploidy rates presented with higher fertilization rates (p < 0.007), higher rates of grade A embryos (p < 0.004) and higher pregnancy rates (p < 0.003), compared to couples with high total aneuploidy rates. CONCLUSIONS: Sperm chromatin condensation and ploidy constitute critical parameters for the evaluation of semen samples before IVF and for the identification of cases in need of ICSI application.

The association of aromatase (CYP19) gene variants with sperm concentration and motility.

The irreversible transformation of androgens into oestrogens is catalysed by cytochrome P450 aromatase. In the present study, we explored the contribution of the (TTTA)(n) polymorphism in the aromatase gene (CYP19) to sperm concentration and motility. Ninety normozoospermic and 60 oligospermic men were examined during infertility examinations. DNA was extracted from spermatozoa, and the CYP19 (TTTA)(n) polymorphism was genotyped by PCR. Genotype analysis revealed six CYP19 (TTTA)(n) alleles with 7-12 repeats. The allelic distribution of the CYP19 (TTTA)(n) polymorphism differed between normozoospermic and oligospermic men (P<0.01). Oligospermic men less frequently had long CYP19 alleles than did normozoospermic men (25 and 37.8%, respectively; P<0.02). The higher frequency of short CYP19 alleles in oligospermic men compared to normozoospermic men (43.3 and 28.3%, respectively; P<0.01) was primarily due to the distribution of the CYP19 (TTTA)(7) allele. The CYP19 (TTTA)(7) allele was associated with lower sperm concentration in normozoospermic men (P<0.01) and in the total study population (P<0.01); it was also associated with lower sperm motility in normozoospermic men (P<0.05) and in the total study population (P<0.01). In conclusion, the CYP19 (TTTA)(7) allele probably impairs aromatase activity, which in turn alters aromatase and oestrogen levels in the testis, leading to decreased sperm concentration and motility. These findings support the significance of cytochrome P450 aromatase in human spermatogenesis and consequently in semen quality.

Association of serum and follicular fluid SHBG levels and SHBG (TAAAA)n polymorphism with follicle size in women undergoing ovarian stimulation.

OBJECTIVE: Sex hormone-binding globulin (SHBG) is the main transport protein of sex steroids. Recently, it has been found to be produced by granulosa lutein cells, suggesting a local role of SHBG in the ovary. The aim of this study was to investigate whether serum and follicular fluid SHBG levels and SHBG (TAAAA)(n) polymorphism are related to follicle size and pregnancy rate in women undergoing in vitro fertilisation. METHODS: The study population consisted of 154 women with tubal and/or male-factor infertility undergoing IVF/ICSI and follicular fluid with oocytes from small (diameter ≤12 mm) and large (diameter ≥18 mm) follicles were studied. Genotyping of SHBG (TAAAA)(n) polymorphism was performed in peripheral blood samples. Serum and follicular fluids were used for hormones determination. RESULTS: Women with short allele genotypes (with less than 8 TAAAA repeats) had higher number of small follicles compared to women with long allele genotypes (5.6 ± 3.9 vs. 3.5 ± 3.2 small follicles, p < 0.003). Follicular fluid SHBG levels correlated positively with serum SHBG levels (p < 0.001) and with the total number of follicles (p < 0.02). Furthermore, small follicles had higher follicular fluid SHBG concentration compared to large follicles (102.9 ± 35.0 nmol/l vs. 85.85 ± 34.88 nmol/l, p < 0.028). CONCLUSION: SHBG levels and the SHBG (TAAAA)(n) polymorphism are associated with follicle size.

Association of paraoxonase gene polymorphisms with sperm parameters.

Paraoxonase (PON) is a high-density lipoprotein-associated enzyme that prevents low-density lipoprotein oxidation. PON proteins, localized in the seminiferous tubules and in spermatozoa, have been implicated in the pathogenesis of male infertility. In the present study, we sought to explore the contribution of the PON gene variants to sperm parameters. One hundred twenty oligospermic and 170 normozoospermic men were examined during infertility investigation. DNA was extracted from spermatozoa, and the PON1(L/M) 55, PON1(Q/R) 192, and PON2(S/C) 311 polymorphisms were genotyped by polymerase chain reaction and digestion with restriction enzymes. The analysis revealed that oligospermic men presented PON1 55L/L, PON1 192Q/Q, and PON2 311S/S genotypes less frequently than normozoospermic men (P < .01, P < .01, and P < .001, respectively), whereas the PON1 55M, PON1 192R, and PON2 311C alleles were significantly increased in oligospermic men (P < .004, P < .008, and P < .008, respectively). The presence of PON1 55L allele was associated with higher sperm motility in oligospermic men (P < .001), in normozoospermic men (P < .01), and in the total study population (P < .01), and the PON1 192Q allele was associated with higher sperm motility in oligospermic men (P < .01), in normozoospermic men (P < .04) and in the total study population (P < .03). On the other hand, the PON2 311S was associated with higher sperm concentration in oligospermic men (P < .03), in normozoospermic men (P < .008), and in the total study population (P < .001). In our series, the PON1 55M and PON1 192R alleles were associated with decreased sperm motility whereas the PON2 311C allele was associated with decreased concentration, supporting the significance of PON genes in semen quality.