Etiology Of Hypospadias Research Articles

Molecular diagnosis in hypospadias

ObjectiveThe aim of this study is to perform a systematic review of the principal genetic and molecular diagnostic methods for hypospadias and their usefulness. MethodsA Pubmed and EMBASE search was carried out using the following MESH terms: “molecular diagnosis”, “genes”, “hypospadias”, “karyotype”, “wgs”, “fish”, “chg”, “sanger”, “microarray”, “mps”, “wes”, and “gwas”.Meta-analyses, systematic reviews, Cochrane reviews, clinical trials, narrative reviews and case series were included, between 2001 and 2016, in both Spanish and English. A total of 33 items were selected for review after reviewing titles, abstracts, and cross references. ResultsHypospadias are the birth defect of the ventral aspect of the penis, accompanied by an ectopic location of the urethral meatus. 30% of all birth malformations in the newborns are urological malformations make up 30% of all birth malformations in newborns. Within the genetic and molecular test available for diagnosis, many are of varying usefulness. These include, among others, karyotyping, FISH, and Sanger sequencing. ConclusionsDue to advances in technology, there are multiple molecular diagnosis methods that can widen the knowledge of the etiology of hypospadias. They also allow them to be used in the everyday practice for a complete study of patients.

Steroid 5-alpha-reductase type 2 (SRD5A2) gene V89L polymorphism and hypospadias risk: A meta-analysis

Hypospadias is a common congenital malformation in males, in which the urethral orifice is found on the ventral side of the penis as a result of incomplete fusion of urethral folds. The etiology of hypospadias is poorly understood, and may be multifactorial, including genetic, endocrine and environmental factors. The steroid 5-alpha-reductase type 2 (SRD5A2) gene, which is mainly expressed in the ventral side of the urethra in the process of male genital development, plays an important role in urethral shaping. To investigate, with database searches of related published papers, whether SRD5A2 gene V89L polymorphism has an association with hypospadias risk. The following databases were searched for relevant papers, and all published case-control studies of hypospadias were used to perform a meta-analysis: PubMed, Embase, Springer Link, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang, and Weipu. A quality assessment was performed using the Newcastle-Ottawa scale of a case-control study. To assess the strength of the association under various genetic models, odds ratio (OR) and its 95% confidence interval (CI) were calculated using fixed-effect or random-effects model according to the heterogeneity. Overall and stratified subgroup analyses, including ethnicity, source of controls, sample for DNA extraction, and hypospadias classification, were performed. All data were analyzed using Review Manager 5.3. This analysis included six eligible case-control studies with 1130 cases and 1279 controls. Overall, there was a statistically significant association between hypospadias risk and V89L polymorphism for allele contrast (C vs G: OR 1.91, 95% CI 1.13-3.23), P=0.02), codominant model (CC vs GG: OR 2.97, 95% CI 1.25-7.04, P=0.01; GC vs GG: OR 2.36, 95% CI 1.35-4.13, P=0.003), dominant model (GC+CC vs GG: OR 2.46, 95% CI 1.28-4.72, P=0.007), and recessive model (CC vs GC+GG: OR 1.91, 95% CI 1.00-3.66, P=0.05). Moreover, there was also a statistically significant association in some subgroups. The positive results are shown in the Summary Table. This meta-analysis suggested that the V89L polymorphism definitely increases the risk of hypospadias, and the C allele is a genetic risk factor for hypospadias occurrence.

Placental pathology and hypospadias.

Studies have shown that hypospadias is associated with placenta-mediated pregnancy complication (PMPC). The role of placental lesions is still unclear. We aimed to examine the association between hyposadias and placental pathology, and the effect of PMPC. Using data from the US Collaborative Perinatal Project in 1959-1966, we identified 15,780 male subjects (167 hypospadias) for analysis. Detailed placental examinations were conducted following a standard protocol. Subjects were divided into two groups according to whether they had PMPC, including small-for-gestational-age, pre-eclampsia/eclampsia or placental abruption. Logistic regression models were used to explore the association. The prevalence of hypospadias was two times higher in subjects with PMPC than those without. Compared to pregnancies with PMPC but no hypospadias, those with both PMPC and hypospadias had significant higher prevalence of placental lesions, such as low placental weight, vascular lesions, villous lesions, and membranous insertion of cord (adjusted odds ratio (OR) ranging from 2.6 to 5.2) after adjusting for potential confounders. In subjects without PMPC, no significant difference of placental pathology was found between those with or without hypospadias. About one third of hypospadias cases were complicated with PMPC and had a higher risk of placental lesions, suggesting heterogeneity of hypospadias etiology and mechanisms.

Diagnóstico molecular en hipospadias

ObjectiveThe aim of this study is to perform a systematic review of the principal genetic and molecular diagnostic methods for hypospadias and their usefulness. MethodsA Pubmed and EMBASE search was carried out using the following MESH terms: “molecular diagnosis”, “genes”, “hypospadias”, “karyotype”, “wgs”, “fish”, “chg”, “sanger”, “microarray”, “mps”, “wes”, and “gwas”.Meta-analyses, systematic reviews, Cochrane reviews, clinical trials, narrative reviews and case series were included, between 2001 and 2016, in both Spanish and English. A total of 33 ítems were selected for review after reviewing titles, abstracts, and cross references. ResultsHypospadias are the birth defect of the ventral aspect of the penis, accompanied by an ectopic location of the urethral meatus. 30% of all birth malformations in the newborns are urological malformations make up 30% of all birth malformations in newborns. Within the genetic and molecular test available for diagnosis, many are of varying usefulness. These include, among others, karyotyping, FISH, and Sanger sequencing. ConclusionsDue to advances in technology, there are multiple molecular diagnosis methods that can widen the knowledge of the aetiology of hypospadias. They also allow them to be used in the everyday practice for a complete study of patients.

Worldwide prevalence of hypospadias

Hypospadias is a common congenital malformation. Surgical repair and management of the long-term consequences require a substantial amount of socioeconomic resources. It is generally accepted that genetic and environmental factors play a major role in the etiology of hypospadias. There have been contradictory reports on rising hypospadias rates, and regional and ethnical differences. The exact prevalence of hypospadias is of major interest for healthcare providers, clinical medicine, and research. To review the literature regarding the worldwide prevalence of hypospadias. Pubmed, EMBASE and Google were systematically screened for: hypospadias, congenital malformation, anomaly, incidence, prevalence, and epidemiology. Exclusion criteria were surgical and risk-factor studies. To give an additional comprehensive overview, prevalence data were harvested from the Annual Report of the International Clearinghouse Centre for Birth Defects Surveillance and Research. Prevalence was reported as per 10,000 live births. Data were available from 1910 to 2013. The median study period was 9 years (range: 1-36 years). Approximately 90,255,200 births have been screened in all studies. The mean prevalence were: Europe 19.9 (range: 1-464), North America 34.2 (6-129.8), South America 5.2 (2.8-110), Asia 0.6-69, Africa 5.9 (1.9-110), and Australia 17.1-34.8. There were major geographical, regional, and ethnical differences, with an extreme heterogeneity of published studies. Numerous studies showed an increasing prevalence; on the other hand, there were a lot of contradictory data on the prevalence of hypospadias. The summary table shows contradictory data from the five largest international studies available. There was huge literature available on the prevalence of hypospadias. Most data derived from Europe and North America. Many methodological factors influenced the calculation of an accurate prevalence, and even more of the true changes in prevalence over time (no generally accepted and standardized definition of hypospadias, different monitoring systems, unclear efficiency of notification and data ascertainment, etc.). There was wide variation of prevalence according to countries and ethnicity, and there were conflicting data on the recent trends of prevalence. Moreover, there weren't any epidemiologic data available from many parts of the world. True prevalence of hypospadias and trends were difficult to estimate. For the future, to be able to assess the true prevalence of hypospadias and changes in prevalence collaboration of national and international prospective registers is recommended.

Expression Analysis of DGKK during External Genitalia Formation

Genetic variants in diacylglycerol kinase κ (DGKK) have been strongly associated with risk of hypospadias. We investigated the expression pattern of Dgkk during development of mouse external genitalia to better understand its function and mechanism in the etiology of hypospadias. We performed Dgkk expression analysis via indirect immunofluorescence in histological sections of CD-1 mouse embryonic and postnatal male, female and diethylsilbestrol treated external genitalia. Histological findings were supplemented with DGKK expression analysis using quantitative real-time polymerase chain reaction assays. In mouse external genitalia Dgkk was expressed in the membrane and cytoplasm of differentiating squamous epithelial cells of urethral plate/groove and epidermis but not in the undifferentiated epithelial cells of preputial lamina or basal layer of urethral groove epithelium. CD-1 gestation day 18male mouse genital tubercle treated with oil or diethylstilbestrol showed similar patterns of Dgkk expression despite many morphological differences, including formation of preputial cleft observed in diethylsilbestrol treated mice. Dgkk appears to be a marker or mediator of squamous cell differentiation during development of mouse external genitalia. However, no association exists between Dgkk expression and formation of preputial cleft in the genital tubercle of diethylsilbestrol treated mice, suggesting that these 2 events may follow independent pathways in mice. Further studies are needed to elucidate the role of DGKK in hypospadias.

Genetic and environmental factors in the aetiology of hypospadias.

This article reviews the current evidence and knowledge of the aetiology of hypospadias. Hypospadias remains a fascinating anomaly of the male phallus. It may be an isolated occurrence or part of a syndrome or field defect. The increasing use of assisted reproductive techniques and hormonal manipulation during pregnancy may have been associated with an apparent rise in the incidence of hypospadias. Genetic studies and gene analysis have suggested some defects that could result in hypospadias. New light has also been thrown on environmental factors that could modulate candidate genes, causing altered development of the male external genitalia.

A MORPHOLOGICAL STUDY OF PLACENTA IN CHILDREN WITH AND WITHOUT HYPOSPADIAS

Abstract Introduction: Hypospadias can be defined as an abnormal urethral orifice under surface of the penis with or without chordee and with or without dorsal hood. At a critical time in sexual differentiation of the male fetus, HCG enters fetal plasma from syncytio trophoblast; acts as an LH surrogate and stimulate replication of testicular Ley dig cells and testosterone synthesis to promote male sexual differentiation. The placental insufficiency may disrupt the supply of nutrients and hcG to the fetus leading to growth retardation and hypospadias. Aim: The aim of this study was to observe and document morphological changes of placenta in children with hypospadias and compare with controls. Materials & Methods: The present study was a case control study from July 2008 to July 2011 The data base of the labor registries of the hospital indicated that there were total 3243 male births during this period. All examined for presence /absence of hypospadias by attending pediatrician. Hypospadias was detected in 17 male newborns. Control cases comprised of 68 male newborns without hypospadias of similar gestational age and birth weight collected by cluster sampling. Result: Total number of male birth during the study period was 3243, in that17 children born with hypospadias. The incidence of hypospadias in our hospital was 0.52%. Gestational age, Birth weight, Placental weight, Placental thickness, Placental volume, volume of infarcts, F.P Ratio, Cord length, were similar in children with hypospadias when compared with controls. CONCLUSION: Fetal factors like gestational age, birth weight, placental weight, Feto-placental ratio were not significantly associated with hypospadias. This study shows no role of placenta in the etiology of hypospadias in children with normal birth weight.

Genetic Polymorphisms in ESR1 and ESR2 Genes, and Risk of Hypospadias in a Multiethnic Study Population

Estrogenic endocrine disruptors acting via estrogen receptors α (ESR1) and β (ESR2) have been implicated in the etiology of hypospadias, a common congenital malformation of the male external genitalia. We determined the association of single nucleotide polymorphisms in ESR1 and ESR2 genes with hypospadias in a racially/ethnically diverse study population of California births. We investigated the relationship between hypospadias and 108 ESR1 and 36 ESR2 single nucleotide polymorphisms in 647 cases and 877 population based nonmalformed controls among infants born in selected California counties from 1990 to 2003. Subgroup analyses were performed by race/ethnicity (nonHispanic white and Hispanic subjects) and by hypospadias severity (mild to moderate and severe). Odds ratios for 33 of the 108 ESR1 single nucleotide polymorphisms had p values less than 0.05 (p = 0.05 to 0.007) for risk of hypospadias. However, none of the 36 ESR2 single nucleotide polymorphisms was significantly associated. In stratified analyses the association results were consistent by disease severity but different sets of single nucleotide polymorphisms were significantly associated with hypospadias in nonHispanic white and Hispanic subjects. Due to high linkage disequilibrium across the single nucleotide polymorphisms, haplotype analyses were conducted and identified 6 haplotype blocks in ESR1 gene that had haplotypes significantly associated with an increased risk of hypospadias (OR 1.3 to 1.8, p = 0.04 to 0.00001). Similar to single nucleotide polymorphism analysis, different ESR1 haplotypes were associated with risk of hypospadias in nonHispanic white and Hispanic subjects. No significant haplotype association was observed for ESR2. The data provide evidence that ESR1 single nucleotide polymorphisms and haplotypes influence the risk of hypospadias in white and Hispanic subjects, and warrant further examination in other study populations.

Geographic analysis of individual and environmental risk factors for hypospadias births.

Hypospadias is a relatively common birth defect affecting the male urinary tract. We explored the etiology of hypospadias by examining its spatial distribution in North Carolina and the spatial clustering of residuals from individual and environmental risk factors. We used data collected by the North Carolina Birth Defects Monitoring Program from 2003 to 2005 to estimate local Moran's I statistics to identify geographic clustering of overall and severe hypospadias, using 995 overall cases and 16,013 controls. We conducted logistic regression and local Moran's I statistics on standardized residuals to consider the contribution of individual variables (maternal age, maternal race/ethnicity, maternal education, smoking, parity, and diabetes) and environmental variables (block group land cover) to this clustering. Local Moran's I statistics indicated significant clustering of overall and severe hypospadias in eastern central North Carolina. Spatial clustering of hypospadias persisted when controlling for individual factors, but diminished somewhat when controlling for environmental factors. In adjusted models, maternal residence in a block group with more than 5% crop cover was associated with overall hypospadias (odds ratio = 1.22; 95% confidence interval = 1.04-1.43); that is living in a block group with greater than 5% crop cover was associated with a 22% increase in the odds of having a baby with hypospadias. Land cover was not associated with severe hypospadias. This study illustrates the potential contribution of mapping in generating hypotheses about disease etiology. Results suggest that environmental factors including proximity to agriculture may play some role in the spatial distribution of hypospadias. Birth Defects Research (Part A) 100:887-894, 2014. © 2014 Wiley Periodicals, Inc.

Prevalence and possible causes of hypospadias

Hypospadias is the most common congenital malformation of the male external genitalia. After the heart and circulatory system, it is the second most common developmental disorder in males. It is due to a midline fusion defect of the male urethra, which results in a misplaced urethral meatus. Hypospadias may be distal, medial and proximal. It may occur as an isolated defect or it may develop together with other genital disorders (retention of testes in one or both sides, microphallus, bifid scrotum) or with malformation of other organs. In some cases syndromic forms may also occur. Genetic factors play a crucial role in the occurrence of early developmental defect, but endocrine and environmental factors may also be important in the aetiology of hypospadias. It may be associated with various sex and autosomal chromosomal abnormalities. Monogenic and chromosomal causes of hypospadias accounts for about in 30% of all cases, while genetic factors remain unknown in 70% of cases. The authors summarize the development of the male external genitalia, the prevalence and possible causes of hypospadias. They propose that better understanding of the pathogenesis of the disease may contribute to the prevention and decreased prevalence of the disease.

Review of genetic and environmental factors leading to hypospadias

Hypospadias is one of the most common congenital malformations, affecting about 4–6 males per 1000 male births, and ranging in severity from a urethral meatus that is slightly off-center to a meatus in the perineal area. Over the past three decades its prevalence may have increased due to changes in reporting of mild cases and/or increased survival of low birth weight infants due to improved neonatal care. However, despite the increasing numbers of males with hypospadias, the overall etiology remains unclear and likely multifactorial in nature. The purpose of this review article is to provide a comprehensive overview of the various factors implicated in hypospadias etiology, including genetic and environmental factors. In addition, we list syndromes in which hypospadias is a relatively common association and delineate the areas that require further investigation in an effort to understand this condition.

Similar causes of various reproductive disorders in early life

During the past few decades, scientific evidence has been accumulated concerning the possible adverse effects of the exposure to environmental chemicals on the well-being of wildlife and human populations. One large and growing group of such compounds of anthropogenic or natural origin is referred to as endocrine-disrupting chemicals (EDCs), due to their deleterious action on the endocrine system. This concern was first focused on the control of reproductive function particularly in males, but has later been expanded to include all possible endocrine functions. The present review describes the underlying physiology behind the cascade of developmental events that occur during sexual differentiation of males and the specific role of androgen in the masculinization process and proper organogenesis of the external male genitalia. The impact of the genetic background, environmental exposures and lifestyle factors in the etiology of hypospadias, cryptorchidism and testicular cancer are reviewed and the possible role of EDCs in the development of these reproductive disorders is discussed critically. Finally, the possible direct and programming effects of exposures in utero to widely use therapeutic compounds, environmental estrogens and other chemicals on the incidence of reproductive abnormalities and poor semen quality in humans are also highlighted.

Twenty-Four Genes are Upregulated in Patients with Hypospadias.

Hypospadias is a congenital hypoplasia of the penis, with displacement of the urethral opening along the ventral surface, and has been reported to be one of the most common congenital anomalies, occurring in approximately 1:250 to 1:300 live births. As hypospadias is reported to be an easily diagnosed malformation at the crossroads of genetics and environment, it is important to study the genetic component in order to elucidate its etiology. In this study, the gene expression profiles both in human hypospadias tissues and normal penile tissues were studied by Human Gene Expression Array. Twenty-four genes were found to be upregulated. Among these, ATF3 and CYR61 have been reported previously. Other genes that have not been previously reported were also found to be upregulated: BTG2, CD69, CD9, DUSP1, EGR1, EIF4A1, FOS, FOSB, HBEGF, HNRNPUL1, IER2, JUN, JUNB, KLF2, NR4A1, NR4A2, PTGS2, RGS1, RTN4, SLC25A25, SOCS3 and ZFP36 (p <0.05). Further studies including genome-wide association studies (GWAS) with expression studies in a large patient group will help us for identifiying the candidate gene(s) in the etiology of hypospadias.

Population Based Nationwide Study of Hypospadias in Sweden, 1973 to 2009: Incidence and Risk Factors

We studied the incidence of hypospadias in Sweden during a 40-year period to determine if changes were associated with known risk factors. We analyzed prospective data from nationwide health care and demographic registers collected for all males (1,948,591 total) born in Sweden between 1973 and 2009. The incidence of hypospadias per 1,000 live-born boys was calculated as number of cases divided by total number of births yearly. The association between hypospadias and risk factors was estimated using logistic regression, expressed as odds ratios. The nationwide incidence of boys diagnosed with hypospadias was approximately 4.5 per 1,000 live-born boys until 1990, increasing to 8 per 1,000 boys during the following decade. Mild and severe phenotypes comprised the increase. Boys born small for gestational age (OR 4.34), as a twin (OR 1.8), as a result of in vitro fertilization (OR 1.15), or with parents from Asia (OR 1.45) or continental Europe (OR 1.41) were at increased risk for hypospadias. Multivariate analyses revealed that changes in risk factors did not explain the increased incidence. However, a systematic change in the classification of the diagnosis in registers could not be ruled out. This nationwide study demonstrates an increased incidence of hypospadias diagnoses in Sweden from 1990 to 1999 that is not attributable to previously known risk factors. The increase includes mild and severe phenotypes, suggesting that shifts in the diagnostic criteria are not the underlying cause.

Literature on the aetiology of hypospadias in the last 5 years: molecular mechanism and environmental factors

Year-by-year, there has been an increasing number of literature on hypospadias, and most of them are mainly focused on two aspects, namely surgical techniques and aetiology, including the molecular mechanism and associated environmental factors. Surgical techniques and nursing levels are being continuously improved. However, in stark contrast, the study of aetiology still lags behind. Up to now, there is still no consensus on the aetiology of hypospadias, including the molecular mechanism and associated environmental factors. To obtain an overall and latest result on the aetiology, we reviewed published literature regarding the aetiology of hypospadias including the molecular mechanism and associated environmental factors in PubMed in the last 5 years. Thirty-seven studies on the aetiology of hypospadias including molecular mechanism and associated environmental factors were found, of which 25 were about associated environmental factors, and they were described according to the aspects of chemicals, parental characteristics, nutrition and hormones. The remaining studies were about the hormone-dependent phase of molecular mechanism, namely androgen-related genes and oestrogen-related genes. Furthermore, the various points of view were classified and discussed in detail.

Hypospadias and Genes Related to Genital Tubercle and Early Urethral Development

We determined whether variants in genes associated with genital tubercle (the anlage for the penis) and early urethral development were associated with hypospadias in humans. We examined 293 relatively common tag single nucleotide polymorphisms in BMP4, BMP7, FGF8, FGF10, FGFR2, HOXA13, HOXD13, HOXA4, HOXB6, SRY, WT1, WTAP, SHH, GLI1, GLI2 and GLI3. The analysis included 624 cases (81 mild, 319 moderate, 209 severe, 15 undetermined severity) and 844 population based nonmalformed male controls born in California from 1990 to 2003. There were 28 single nucleotide polymorphisms for which any of the comparisons (ie overall or for a specific severity) had a p value of less than 0.01. The homozygous variant genotypes for 4 single nucleotide polymorphisms in BMP7 were associated with at least a twofold increased risk of hypospadias regardless of severity. Five single nucleotide polymorphisms for FGF10 were associated with threefold to fourfold increased risks, regardless of severity. For 4 of them the results were restricted to whites. For GLI1, GLI2 and GLI3 there were 12 associated single nucleotide polymorphisms but results were inconsistent by severity and race/ethnicity. For SHH 1 single nucleotide polymorphism was associated with a 2.4-fold increased risk of moderate hypospadias. For WT1 6 single nucleotide polymorphisms were associated with approximately a twofold increased risk, primarily for severe hypospadias. This study provides evidence that single nucleotide polymorphisms in several genes that contribute to genital tubercle and early urethral development are associated with hypospadias risk.

Quantitative measurement of the androgen receptor in prepuces of boys with and without hypospadias

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Despite diverse anatomical and histological trials in humans and animal models, the aetiology of hypospadias remains unknown and currently there is no clear molecular explanation about the emergence of this disease; however, genetic, endocrine and environmental mechanisms have been suggested. The aim of the present study was to quantify and compare the androgen receptor (AR; mRNA and protein) levels in 40 prepuces of boys with and without hypospadias using quantitative real-time polymerase chain reaction, Western Blot and standardised, automated immunohistochemistry. AR mRNA (P = 0.013) and AR protein (P = 0.014) was significantly elevated in the prepuces of boys with hypospadias compared with boys without hypospadias. Altogether our data indicate that elevated AR mRNA and protein levels can be considered as a biochemical response of an AR signalling defect as an identified cause in boys with hypospadias. Additionally, nuclear staining intensity for AR-protein in specimens of boys with hypospadias was higher than in boys with phimosis. To address the role of the androgen receptor (AR) on mRNA and protein levels in prepuces of boys with and without hypospadias. Data from 40 foreskin specimens of consecutive circumcised boys (20 with vs 20 without hypospadias) were enrolled in this prospective study. After surgery, samples were fixed in formaldehyde and frozen in liquid nitrogen. Total RNA was isolated from frozen tissue and transcribed to complementary DNA. The amount of AR mRNA was measured by quantitative real-time polymerase chain reaction and Western Blot and standardised, automated immunohistochemistry were used to assess AR protein levels. The mean age at time of surgery was 61.8 and 30.9 months in boys without and with hypospadias, respectively. There was penile, coronal and sine hypospadias in seven (35%), nine (45%), and four (20%) boys, respectively. AR mRNA was significantly elevated in the prepuces of boys with hypospadias compared with boys without hypospadias, at a mean (sd) of 28.33 (5.39) vs 15.31 (1.85) (P = 0.013). Furthermore, the amount of AR protein was higher in boys with, compared with boys without hypospadias, at a mean (sd) of 133.25 (6.17) vs 100 (4.45) (P = 0.014). Different AR mRNA expression and protein levels seem to be an indication of an AR signalling defect as a cause in boys with hypospadias. Decreased AR DNA binding and functional capability may result in a compensatory up-regulation of both AR mRNA and protein. Further studies are necessary to perform structural analysis of the AR and to corroborate these preliminary findings.

Activating transcription factor 3 is not up-regulated in hypospadias patients in Japan

The aetiology of hypospadias is largely uncharacterized. Some of the researchers have advocated that activating transcription factor 3 (ATF3), an oestrogen-responsive transcription factor, is up-regulated in patients with hypospadias. The purpose is to evaluate the universality of this fact; we studied the expression of ATF3 protein in prepuce tissue obtained from hypospadias and phimosis patients living in metropolitan Tokyo. Prepuce tissue was obtained from outer foreskin at the time of surgery, quickly prepared for paraffin-embedded sectioning and stained immunohistochemically for ATF3. Two researchers blindly evaluated immunoreactivity and scored it semi-quantitatively as nil = 0, weak = 1, or strong = 2, to give a final staining intensity score (SIS). Subjects were 18 hypospadias patients and 17 phimosis patients (as controls) who had surgery between January, 2009 and March, 2010. All subjects lived in metropolitan Tokyo, Japan. Mean ages at surgery were 2.9 ± 1.0 and 3.9 ± 2.4 years, respectively (P > 0.05). SIS was not statistically different between hypospadias patients (1.4 ± 0.5) and controls (1.5 ± 0.5), (P > 0.05). Our data suggest that ATF3 is not highly associated with hypospadias in metropolitan Tokyo. Differences in ethnicity might have influenced our results.

ATF3 rSNPs, transcriptional factor binding sites and human etiology

Three rSNPs (rs3125289, rs1877474 and rs11119982) in one intron of the activating transcription factor 3 (ATF3) gene have been significantly associated with the human etiology of hypospadias and may be associated with human disease. These rSNP alleles alter the DNA landscape for potential transcriptional factors (TFs) to attach resulting in changes in transcriptional factor binding sites (TFBS). These TFBS changes are examined with respect to the human etiology of hypospadias which has been found to be significantly associated with the rSNPs.