Lucia Fischetti

Linkage analysis in keratoconus: replication of locus 5q21.2 and identification of other suggestive loci.

PURPOSE Keratoconus (KC) is the most common indication for corneal transplantation in the Western world, with etiologic mechanisms still poorly understood. The disease prevalence in the general population is approximately 1:2000, and familial aggregation, together with increased familial risk, suggests important genetic influences on its pathogenesis. To date, several loci for familial keratoconus have been described, without the identification of any responsible gene in the respective mapped intervals. The aim of this study was to identify causative/susceptibility genes for keratoconus. METHODS A total of 133 individuals (77 affected and 59 unaffected) of 25 families from southern Italy were genotyped using microsatellite markers and included in a genome-wide scan. Nonparametric and parametric analysis using an affected-only strategy were calculated by using genetic algorithm software. RESULTS The chromosomal regions 5q32-q33, 5q21.2, 14q11.2, 15q2.32 exhibited the strongest evidence of linkage by nonparametric analysis (NPL = 3.22, 2.73, 2.62, and 2.32, respectively). The regions 5q32-q33 and 14q11.2 were also supported by multipoint parametric analysis, for which heterogeneity LOD (HLOD) scores of 2.45 (alpha = 0.54) and 2.09 (alpha = 0.46), respectively, were obtained under an affected-only dominant model. CONCLUSIONS This study represents the first KC linkage replication study on the chromosomal region 5q21.2 and reports evidence of suggestive linkage in several regions for which suggestive or significant linkage has been previously detected in different populations.

Large rearrangements detected by MLPA, point mutations, and survey of the frequency of mutations within the SLC3A1 and SLC7A9 genes in a cohort of 172 cystinuric Italian patients

Cystinuria is a rare inherited disorder characterized by defective renal reabsorption of cystine and the dibasic amino acids. SLC3A1 and SLC7A9 have been identified as responsible genes. The large majority of the more than 200 mutations so far identified in the two genes are point mutations, while only few alleles carrying gross genomic alterations have been reported. We screened 39 cystinuric patients for large rearrangements, by two home-made multiplex ligation-dependent probe amplification (MLPA) assays. MLPA analysis led to the identification of 6 different alleles in SLC3A1 and 2 in SLC7A9 accounting for a total of 25 copy number changes, 11 in SLC3A1 and 14 in SLC7A9. Three large rearrangements in SLC3A1, deletion of exons 2-4 (E2_E4del), deletion of exons 5-6 (E5_E6del) and duplication of exons 8-9 (E8_E9dup) are novel. A complete SLC7A9 gene deletion was found in three patients. In addition, we report the identification of three novel point mutations in SLC7A9 (p.G105E, p.R250K, c.1416_1417insAC), the frequency and the occurrence of cystinuria mutations in a cohort of 172 Italian patients. In conclusion, we developed a reliable and robust MLPA analytic method for SLC3A1 and SLC7A9 genes that represents an optimal complement to DNA sequence analysis in patients with cystinuria, enabling the screening for deletions and duplications.

Risk of obstetric and thromboembolic complications in family members of women with previous adverse obstetric outcomes carrying common inherited thombophilias.

Summary.  Background: Factor (F)V Leiden and the prothrombin 20210A mutation (PTm) are associated with the occurrence of obstetric complications, including pregnancy‐related venous thromboembolism (VTE). It is not known whether family members of women with FV Leiden or PTm and previous obstetric complications have a higher risk of VTE or adverse obstetric outcomes. Methods: A retrospective family study including 563 relatives of 177 women with previous adverse outcomes carrying FV Leiden or PTm, referred between April 1993 and June 2010. A history of obstetric complications and VTE was obtained. Prevalence of VTE and obstetric complications in relatives with and without inherited thrombophilias was compared. Adjusted odd ratios (OR) and 95% confidence intervals (CI) were calculated using logistic regression models that controlled for predictors (age, FV Leiden and PTm). Results: Relatives carrying FV Leiden had a significant and independent risk for obstetric complications (OR: 1.98, 95% CI 1.03–3.83); this risk was not observed in the presence of PTm (OR: 1.03, 95% CI 0.46–2.32). The presence of FV Leiden or PTm in heterozygosis was significantly and independently associated with the occurrence of VTE (OR: 5.2, 95% CI: 1.70–15.91). Severe thrombophilias were strong risk factors for VTE (OR: 23.2, 95% CI: 6.0–89.85). Male gender was a significant and independent risk factor for VTE (OR: 3.49, 95% CI: 1.51–8.05). The risk did not change when relatives of women with a previous pregnancy‐related VTE were excluded (OR: 3.49, 95% CI: 1.51–8.05). Conclusions: Knowledge of thrombophilia status may help to better define the obstetric and thromboembolic risks in asymptomatic family members of women who suffered from obstetric complications.

Twenty-four novel mutations identified in a cohort of 85 patients by direct sequencing of the SLC3A1 and SLC7A9 cystinuria genes.

Mutations in the SLC3A1 and SLC7A9 genes cause cystinuria (OMIM 220100), an autosomal recessive disorder of amino acid transport and reabsorption in the proximal renal tubule and in the epithelial cells of the gastrointestinal tract. In an attempt to characterize the molecular defect in the SLC3A1 and SLC7A9 genes, we analyzed a cohort of 85 unrelated subjects clinically diagnosed as affected by cystinuria on the basis of stone formation, prevalently of Italian and Greek origin. Analysis of all coding region and exon-intron junctions of the SLC3A1 and SLC7A9 genes by using direct sequencing method allowed us to identify 62 different mutations in 83 out of 85 patients accounting for 90.5% of all affected chromosomes. Twenty-four out of 62 are novel mutations, 9 in SLC3A1 and 15 in SLC7A9. In conclusion, this report expands the spectrum of SLC3A1 and SLC7A9 mutations and confirms the heterogeneity of this disorder.

Low-molecular -weight heparin in pregnancies after ART -A retrospective study-

INTRODUCTION The utility of an antithrombotic prophylaxis in Assisted Reproductive Technologies (ART) is highly debated. It has been hypothesised that specific effects of heparin on the coagulation system during implantation can improve the number of clinical pregnancies and live births. MATERIALS AND METHODS We studied a cohort of 327 women undergone at least 1 ART cycle before thrombophilia testing. Overall, a number of 751cycles was analysed. Low-Molecular-Weight Heparin (LMWH) and/or low-dose aspirin (ASA) were prescribed in 132 (17.6%) cycles. Furthermore, all the women underwent thrombophilia screening. RESULTS The univariate analysis showed that LMWH with/without ASA was significantly associated with both the outcomes clinical pregnancy and live birth, while the use of ASA was not associated with live birth. The logistic regression showed that the use of LMWH was significantly associated with both the outcomes, clinical pregnancy (OR: 6.0, 95%CI: 2.8-15.6) and live birth (OR: 10.7, 95%CI: 3.2-36.1). The type of ART procedure significantly influenced the likelihood of achieving clinical pregnancy. CONCLUSIONS Present findings suggest that LMWH alone or combined with ASA could have a role in fostering the implantation of embryos and improving the number of live births after ART.

Clinical Utility of Antithrombotic Prophylaxis in ART Procedures: An Italian Experience

Background The usefulness of antithrombotic prophylaxis in management of Assisted Reproductive Technologies (ART) is questionable. Objectives We prospectively examined the contribution of an antithrombotic prophylaxis in influencing clinical pregnancy and live-birth in an unselected cohort of women approaching ART. Patients/Methods 1107 women with fertility problems and a valid indication for ART were recruited. Baseline and follow-up information of obstetric outcomes and antithrombotic treatment were collected. Results and Conclusions Median follow-up time was 34.5 months (range: 2–143). During the follow-up period, 595 (53.8%) women underwent ART (total 1234 cycles); 202 (33.9%) women achieved a pregnancy for a total of 255 clinical pregnancies. The concomitant use of LMWH and aspirin was significantly associated with a higher rate of clinical pregnancies (p: 0.003, OR: 4.9, 95% CI: 1.7–14.2). The pregnancy rate was also significantly increased by the use of LMWH alone (p: 0.005, OR: 2.6, 95% CI: 1.3–5.0). Carriership of inherited or acquired thrombophilia did not affect clinical outcomes of the ART. The efficacy of antithrombotic treatment was confirmed when the outcome “ live-birth” was considered. Present data suggest a potential benefit of antithrombotic prophylaxis during ART in improving the number of live-births.

Venous thromboembolism in assisted reproductive technologies: comparison between unsuccessful versus successful cycles in an Italian cohort

Pregnancies after assisted reproductive technologies (ART) have been associated with an increased risk of venous thromboembolism (VTE). On the contrary, the magnitude of this risk in unsuccessful ART cycles (not resulting in a clinical pregnancy) has not yet been clearly defined. In this study, we evaluated the incidence of VTE in unsuccessful cycles and compared it with that recorded in successful cycles in the same study population. From a cohort of 998 women consecutively referred by local Fertility Clinics to our Atherosclerosis and Thrombosis Unit (April 2002–July 2011), we identified and included women with at least one cycle of ovarian stimulation and a negative history for VTE. Overall, 661 women undergone 1518 unsuccessful and 318 successful cycles of ovarian stimulation, respectively, were analysed. VTE events occurred in 2/1518 (1.3‰) unsuccessful cycles compared with 3/318 (9.4‰) successful cycles, (Two-tailed Fisher exact test, p = 0.04, OR 0.14, 95% CI 0.02–1.02). Both cases observed in unsuccessful cycles were isolated pulmonary embolism occurred after OHSS; no antithrombotic prophylaxis had been prescribed. At logistic regression analysis, the occurrence of successful cycle and BMI were significantly and independently associated with the occurrence of VTE with an OR of 13.94 (95% CI 1.41–137.45) and 1.23 (95% CI 1.01–1.49), respectively. VTE incidence is significantly lower in unsuccessful cycles as compared to that of successful ones. However, although rare, thrombotic risk during ovarian stimulation cannot be excluded and, when it occurs, can be life-threatening. Therefore, particular attention should be paid to these women, independently of ART outcome.

Factor VII deficiency: a novel missense variant and genotype-phenotype correlation in patients from Southern Italy

This study aimed at attempting to correlate genotype and phenotype in factor VII deficiency. Here, we present molecular and clinical findings of 10 patients with factor VII deficiency. From 2013 to 2016, 10 subjects were referred to our center because of a prolonged prothrombin time identified during routine or presurgery examinations or after a laboratory assessment of a bleeding episode. Mutation characterization was performed using the bioinformatics applications PROMO, SIFT, and Polyphen-2. Structural changes in the factor VII protein were analyzed using the SPDB viewer tool. Of the 10 variants we identified, 1 was responsible for a novel missense change (c.1199G>C, p.Cys400Ser); in 2 cases we identified the c.-54G>A and c.509G>A (p.Arg170His) polymorphic variants in the 5′-upstream region of the factor VII gene and exon 6, respectively. To our knowledge, neither of these polymorphic variants has been described previously in factor VII-deficient patients. In silico predictions showed differences in binding sites for transcription factors caused by the c.-54G>A variant and a probable damaging effect of the p.Cys400Ser missense change on factor VII active conformation, leading to breaking of the Cys400-Cys428 disulfide bridge. Our findings further suggest that, independently of factor VII levels and of variants potentially affecting factor VII levels, environmental factors, e.g., trauma, could heavily influence the clinical phenotype of factor VII-deficient patients.

OC-19 Antithrombothic prophylaxis and ART procedures: an Italian prospective cohort study

Assisted reproductive technologies (ART) have been widely used in couples suffering from infertility. The clinical pregnancy rate is low, varying from 20 to 35% per cycle started. The role of antithrombotic drugs in improving pregnancy rate is controversial, although some Fertility Clinics have adopted different protocols either in thrombophilic and non-thrombophilic women. Between March 1998 and July 2011 we prospectively evaluated a cohort of 1107 women approaching ART (2214 cycles) consecutively referred to our Thrombosis Unit (S. Giovanni R.). All were investigated for inherited and acquired thrombophilias. Median follow-up was 34.53 months (range 2–143 months). At the enrolment, 327 women (29.5%) have experienced 946 ART cycles. One hundred twenty-two (37.3%) women obtained a clinical pregnancy (176 pregnancies), with 21 (16%) live-born children. Overall, 115 (10.4%) women carried al least one thrombophilia (45 the FVL, 57 the PTm, 13 severe thrombophilias). After screening, 595 (53.8%) underwent at least 1 attempt (1268 cycles, 27 lost to follow-up). In 424 (33.4%) cycles an antithrombotic prophylaxis (342 treated with aspirin, 66 with LMWH, 16 with aspirin+LMWH) was used. Pregnancy rate was 21.4% (265/1241 cycles) with 171 (13.8%) live-born children. Clinical pregnancies were not significantly different in treated vs untreated cycles (p: 0.42, OR: 1.1, 95% CI: 0.8–1.5). The rate of live-born was not significantly different in treated vs untreated cycles (p: 0.73, OR: 0.9, 95% CI: 0.6–1.3) prophylaxis. Overall, 7 thrombotic events (3 PE, 3 DVT, 1 arterial thrombosis; 6 of them in untreated women) were observed. Among them, 4 (0.3%, 2 DVT, 2 PE) occurred after screening, only 1 during LMWH prophylaxis. In women undergoing ART procedures, the use of antithrombotic prophylaxis is not associated with an improved pregnancy rate or live-born children. Thrombotic complications are less frequent in women receiving an antithrombotic prophylaxis