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Ring chromosome 13 is a rare genetic condition with an incidence of 1/58,000 in live births. Major clinical features of patients with ring chromosome 13 include growth and developmental retardation, microcephaly, facial dysmorphism, ambiguous genitalia, anal atresia, eye malformations, retinoblastoma, and hand, foot, and toe abnormalities. The severity of the phenotype depends on the amount of genetic material lost during ring chromosome formation. Here, we report 2 cases with ring chromosome 13 at either end of the phenotypic spectrum. [ABSTRACT FROM AUTHOR]

Intersexual genetic correlations are expected to constrain the evolution of sexual dimorphic traits, including the degree of sex-biased gene expression. Consistent with that expectation, studies in fruit flies and birds have reported that genes whose expression has a strong intersexual genetic correlation (rMF) show a lower level of sex-biased expression (SBE). However, it is known that both rMF and SBE can be affected by the environment. It is therefore unclear whether there is a consistent relationship between these 2 quantities across multiple environments. In this paper, we study this relationship in the African malaria mosquito Anopheles gambiae. We show that both rMF and SBE change between environments. The change in SBE across environments is significantly correlated with dN/dS: greater changes in SBE are associated with higher values of dN/dS. Furthermore, the relationship between rMF and SBE is sensitive to the environment. We conclude that this relationship is sufficiently plastic that environmental effects should be considered in future studies. [ABSTRACT FROM AUTHOR]

Sexual differences are often dramatic and widespread across taxa. Their extravagance and ubiquity can be puzzling because the common underlying genome of males and females is expected to impede rather than foster phenotypic divergence. Widespread dimorphism, despite a shared genome, may be more readily explained by considering the multivariate, rather than univariate, framework governing the evolution of sexual dimorphism. In the univariate formulation, differences in genetic variances and a low intersexual genetic correlation ( [ABSTRACT FROM AUTHOR]

WT1 mutations have been described in a variety of syndromes, including Denys-Drash syndrome (DDS), which is characterized by predisposition to Wilms' tumor, genital abnormalities and development of early nephropathy. The most frequent WT1 defects in DDS are missense mutations located in exons 8-9. Our aim is to report a novel WT1 mutation in a 46,XY patient with a DDS variant, who presented a mild nephropathy with a late onset diagnosed during adolescence. He had ambiguous genitalia at birth. At 4 months of age he underwent nephrectomy (Wilms' tumor) followed by chemotherapy. Ambiguous genitalia were corrected and bilateral gonadectomy was performed. Sequencing of WT1 identified a novel heterozygous mutation (c.742A>T) in exon 4 that generates a premature stop codon (p.K248X). Interestingly, this patient has an unusual DDS nephropathy progression, which reinforces that patients carrying WT1 mutations should have the renal function carefully monitored due to the possibility of late-onset nephropathy. [ABSTRACT FROM AUTHOR]

A 16-year-old female patient presented with complaints of amenorrhea and lack of breast development. Baseline hormonal results were consistent with primary ovarian failure. Ovaries and uterus could not be demonstrated by ultrasonographic evaluation. No deletion-type mutation was detected in the SRY gene of the patient whose karyotype was 46, XY. The gonads, both of which were detected as streaks during laparoscopy, were removed because of the risk for gonadal tumour. Hormone replacement therapy was started following bilateral gonadectomy. With this case report, we aimed to underline the necessity of considering 46, XY complete pure gonadal dysgenesis in the differential diagnosis in every adolescent female patient with delayed puberty and the importance of early gonadectomy in order to avoid the risk for gonadal tumuor development. [ABSTRACT FROM AUTHOR]

This article summarizes the current state of research on Sexual Quality of Life (SexQoL) of adults with 46,XY Disorders of Sex Development (DSD)/Intersexuality. An extensive literature search yield 21 studies published between 1974-2007, examining sexual aspects in individuals with 46,XY DSD. However, many of them lack methodological quality. The results are inconsistent but overall indicate that SexQoL of individuals with 46,XY DSD is impaired, particular with regard to sexual dysfunctions and sexual satisfaction. Future studies on SexQoL should focus more on qualitative aspects of sexuality and investigate medical and psychosocial risk factors such as sex-corrective surgery and parental bonding. [ABSTRACT FROM AUTHOR]

Gynodioecy, where females co-occur with hermaphrodites, is a relatively common sexual system in plants that is often the result of a genetic conflict between maternally inherited male sterility genes in the mitochondrial genome and the biparentally inherited male fertility restorer genes in the nucleus. Previous models have shown that nuclear-cytoplasmic gynodioecy can be maintained under certain conditions by negative frequency-dependent selection, but the effect of other evolutionary processes such as genetic drift and population subdivision is only partially understood. Here, we investigate the joint effects of frequency-dependent selection, drift, and migration through either pollen or seeds on the maintenance of nuclear-cytoplasmic gynodioecy in a subdivided population. We find that the combination of drift and selection causes the loss of gynodioecy under scenarios that would maintain it under the influence of selection alone, and that both seed and, more surprisingly, pollen flow can maintain the polymorphism. In particular, although pollen flow could not avoid the loss of cytoplasmic polymorphism within demes, it allowed the maintenance of nuclear-cytoplasmic polymorphism at the metapopulation level. [ABSTRACT FROM AUTHOR]

Schistosomes are the cause of the most significant helminth disease of humans. Their unusual sexual biology is intriguing. Instead of being hermaphroditic, as is the rule in other trematode species, they are gonochoric. Furthermore, their mating system is considered to be monogamous, a characteristic shared by only 1% of living species, and their sex ratio is male-biased. In this paper we propose an explanation of the origin of the male-biased sex ratio in schistosomes and highlight the ecological and evolutionary consequences of this bias. We argue that schistosome gonochorism, monogamy and the biased sex ratio can be integrated into a single evolutionary scheme. [Copyright &y& Elsevier]

Male gain curves describe the relationship between allocation to sperm production and male reproductive success and are central to models of sex allocation in hermaphrodites. Sperm competition is expected to result in more linear gains and select for increased allocation. We hypothesized that high sperm production in passively mating systems may also be the result of selection to enhance the ability to fertilize distant ova. Consequently, we explored the effect of distance on male gain curves in a free-spawning colonial ascidian. The performance of focal males that varied in sperm production was assayed at three distances via microsatellite markers. An advection-diffusion model was used to estimate sperm concentration gradients, to predict male reproductive gain integrated across multiple downstream females, and explore effects of hydrodynamic conditions. As distance increased, male reproductive success decreased and empirical gain curves became increasingly linear. Our model predicted that the expected net gain curve is relatively insensitive to variation in flow regime and will saturate much more slowly than if only a single, nearby distance is considered. Thus, high levels of sperm production may enhance fitness both in competitive situations and with increasing fertilization distance, highlighting the need to consider distance effects when evaluating gain curves. [ABSTRACT FROM AUTHOR]

Individuals with male phenotypes and 46 XX karyotype appear in about 1 of 20,000 births with clinical features varying from normal male appearance to sexual ambiguity and hermaphroditism. More than 80% of these patients present a spontaneous translocation of the SRY gene from the Y to the X chromosome in the paternal germinal cells. We present a case of a 2 years old boy diagnosed with minor hypospadias, bifid scrotum, normal penis and palpable gonads in the scrotum. The karyotype is 46 XX and FISH analysis reveals SRY translocation on one of the X chromosomes. Ultrasound exam does not reveal any mullerian structures and a hCG test proves the testes to be functional. A short course of treatment with hCG is recommended in order to induce the proper development of the scotal sac. The patient will need monitoring, in order to identify the development of hypergonadic hypogonadism, which characterizes such patients in later life. This case underlines the importance of comprehensively investigating any patient with even minor genitalia anomalies. [ABSTRACT FROM AUTHOR]

The article focuses on a study which reconstructs the rate of genetic recovery of the population of the hermaphroditic mangrove, Avicennia alba, in Mekong Delta 30 years after the use of Agent Orange, which is a mixture of phenoxyl herbicides. It evaluates the age of Avicennia alba with the use of models based on internode growth and genotypes samples for six microsatellite loci. It also compares the reconstructed evolution of genetic diversity since local extinction with the genetic diversity of an unaffected population from Thailand. Results show that genetic diversity of the population is increasing in Mekong Delta. However, the population is reaching an asymptotic level that is comparable to the Thai population.

Objectives: To determine the mechanism for the 46,XX/46,XY karyotype observed in a patient with an ovotesticular disorder of sexual development (ie, true hermaphroditism). Methods: Cytogenetic, molecular cytogenetic, and molecular DNA analyses were performed on the blood, skin, and left and right gonadal tissue from 2 surgical procedures. The results of these studies were used to determine whether the ovotesticular disorder of sexual development resulted from mosaicism or tetragametic chimerism. Results: Cytogenetic and molecular analyses revealed a mixture of 46,XX and 46,XY cells in most tissues. DNA analysis from the gonadal tissues from surgeries 1 and 2 was performed. Highly polymorphic loci from 12 different chromosomes were examined for the presence of ≥1 paternal or maternal alleles. Three loci were highly informative: D14S544 (14q32.2), DS14S583 (14q21.3), and SE33 (6q14). Each demonstrated the presence of 2 paternal and 2 maternal alleles, indicating that the ovotesticular disorder of sexual development resulted from tetragametic chimerism. Conclusions: Based on the findings of the cytogenetic, molecular cytogenetic, and DNA analyses of the polymorphic markers from several different loci, it was confirmed that the patient had tetragametic chimerism. This case has assisted in increasing our knowledge of the possible mechanisms causing this rare and complex disorder. [Copyright &y& Elsevier]

Congenital adrenal hyperplasia (CAH) is a group of potentially life-threatening disorders, most often caused by deficiency of steroid 21-hydroxylase. Children with ambiguous genitalia, hermaphroditism, or signs and symptoms of CAH admitted to Children’s Medical Center were enrolled in the survey, and 101 patients were found. Karyotyping, clinical examination, and paraclinical tests were done. HLA typing was done in patients with proven classical CAH and their parents. HLA antigens were typed in children with CAH-type 21-hydroxylase deficiency. The antigen frequencies were compared with those of the control population. The studies revealed that two HLA antigens, HLA-B18 and HLA-B21, showed a significant increase in frequency. The calculated relative risk value was high, distinguishing the population of patients and their parents. The relative risk among patients was 11.82 for HLA-B18 and 1.75 for HLA-B21 antigens. There was no relationship between HLA-DR antigens and CAH. Studies on the correlation between HLA and CAH indicate an association with HLA-B18 and HLA-B21 antigens, and they can be used as genetic markers of the disorder in the Iranian population, if they are restricted to Iranian patients. [ABSTRACT FROM AUTHOR]

Mating behavior, including courtship and copulation, is a main component of male fitness, especially in species with no parental care. Variation in this behavior can thus be a target for mate choice and sexual selection, and can lead to evolution. The fruit fly, Drosophila melanogaster, has well-documented complex male courtship comprised of a sequence behaviors, and is an ideal model for behavior-genetic analysis. In order to evaluate genetic differences in the temporal pattern of mating behavior, we developed a high-throughput method that allows us to document the progression of male courtship and copulation using an ordinal scale (male mating progression scale, MMP). Using this method, we document natural genetic variation in the temporal pattern of behavior that was not detected using other metrics. This method was robust enough to detect genetic variation in this trait for males placed with both virgin and mated female targets. [ABSTRACT FROM AUTHOR]

Some species display intersex variation in their rate of meiotic recombination, where recombination is usually suppressed in the heterogametic sex. Although no heteromorphic sex chromosomes have been detected in zebrafish (Danio rerio), genetic analysis has indicated a lower frequency of recombination in males relative to females. Our study of the meiotic recombination pattern in female zebrafish indicates that adult females have only a few meiotic oocytes that are found in groups in the ventral zone of the ovarian surface. We used antibody staining of human mutL homolog 1 (MLH1) protein to mark the sites of putative chiasmata to seek a physical basis for the pattern of recombination and its relative frequency in both sexes. We report that MLH1 foci are found mostly in distal regions of the synaptonemal complexes (SCs) in males, but tend to be more evenly distributed in females. Our cytological analysis yields a ratio of MLH1 foci per chromosome in males versus females of 1:1.55. This lower level of recombination in males is in general agreement with previously published results from linkage map analysis. However, the similar ratio of MLH1 foci per unit length of SCs in both sexes demonstrates a correlation between SC length and the frequency of recombination rather than a mechanism that suppresses recombination in males. Thus, chiasma interference seems to provide similar expression in males and females in agreement with the situation in humans, where oocytes with longer SCs display a higher level of recombination that is not a consequence of more closely spaced crossovers along the SCs.Heredity (2008) 100, 489–495; doi:10.1038/sj.hdy.6801091; published online 5 March 2008 [ABSTRACT FROM AUTHOR]

The article discusses the examination of the surgical interventions used to correct an intersexed condition, one previously known as hermaphroditism, and the pressure on parents to choose one sex or the other. It examines two principle technologies of intersex such as current medical protocols, and web sites constructed by and for people with intersex. The subject positions delineated by web-based intersex texts and practices reiterate, renegotiate, and refigure the medicalized bodies and identities inscribed in the medical literature. In the second part, the author looks at the way some intersexed women use the World Wide Web to advocate for the rights of their community and resist medicalization.

Angiosperms show an evolutionary trend from an indefinite to a fixed number of floral organs. When floral formula inconstancy in recent angiosperms is reported, it is often considered as a byproduct of stress and its fitness consequences remain mostly unexplored. We report substantial nonhomeotic meristic variation in stamen number (0–10 stamens per flower) in two populations of Hormathophylla spinosa during four years. This variation was plastic, suggesting its functional role in the adjustment of phenotypic gender. However, no correlations were found between phenotypic gender and plant size, pollinator or herbivore abundance. Effects on female reproductive success were inconsistent on a per-flower and on a per-plant basis, rendering adaptive explanations in terms of selfing or resource adjustment unsatisfactory with the data available. Nevertheless, individuals showing larger interannual variation in phenotypic gender showed higher female reproductive success, suggesting an advantage for gender modification. Although our results do not easily conform to any adaptive explanation, this remarkable example of breakdown of trait canalization should stimulate the study of the mechanisms and ultimate causes responsible for the maintenance of fixed floral traits. [ABSTRACT FROM AUTHOR]

We used sets of meta-analyses to review the evidence of sex-biased herbivory in dioecious plants as well as intersexual differences in plant characteristics that might affect herbivores. Thirtythree studies were reviewed to assess the effects of plant sex on herbivore abundance, survivorship and damage imposed to host plants, whereas 54 studies were reviewed for the effects of plant sex on plant morphological, physiological, and nutritional characteristics. The standardized mean difference between males and females was chosen as the measure to calculate effect sizes. Male plants exhibited significantly higher numbers of herbivores (d++=1.074) and significantly higher herbivory measured in terms of plant damage (d++=0.577) compared to female plants. Effects of plant sex on herbivore abundance were stronger for folivores and gallformers compared to the other guilds, whereas effects of plant sex on herbivore damage were stronger for flower predators compared to browsers and folivores. No difference in herbivore survivorship was observed between sexes. Male plants exhibited significantly more leaves (d++=0.202), larger leaves (d++=0.91), fewer flowers (d++=−0.89) and longer stems (d++=0.614) than female plants. Although male plants exhibited significantly lower concentrations of secondary compounds (d++=−0.209) and other defenses (d++=−0.53) than female plants, no difference in nutrient concentration, such as foliar nitrogen, was observed between sexes. [ABSTRACT FROM AUTHOR]

Unlabelled: About 50% of intersex cases are due to male pseudohermaphroditism, and of these cases, 50% are not clarified aetiologically. The association of idiopathic male pseudohermaphroditism and prenatal growth retardation has been recently reported. The aim of this study was to verify whether there was a difference in weight and/or length at birth between idiopathic and non-idiopathic male pseudohermaphroditism patients. A total of 70 patients with male pseudohermaphroditism were recruited; 35 non-idiopathic and 35 idiopathic. Birth weight and length were converted to z scores, and the severity of genital ambiguity was classified according to Prader grades: less virilized (Prader 1 to 3) and more virilized (Prader 4 or 5). Data were analysed using a Mann-Whitney test, odds ratio and logistic regression analysis. Birth weight (P = 0.028) and length (P = 0.01) z scores were lower in the idiopathic male pseudohermaphroditism group compared to the non-idiopathic group and were also significantly decreased among the less virilized patients, both in the sample as a whole (weight z score, P = 0.002; length z score, P = 0.0008) and in the group of idiopathic patients (weight z score, P = 0.013; length z score, P = 0.007). According to logistic regression analysis, only birth length z score significantly predicted the severity of the genital ambiguity in patients with idiopathic male pseudohermaphroditism ( P = 0.0007).Conclusion: There is an association between prenatal growth retardation and male pseudohermaphroditism which may be due to genetic factors not clarified yet or to environmental factors which act early in gestation. [ABSTRACT FROM AUTHOR]

Abstract: The copulatory neuromuscular system of lizards is highly sexually dimorphic. Adult males possess bilateral penises called hemipenes, which are independently controlled by two muscles, the retractor penis magnus (RPM) and transversus penis (TPN). These structures are not obvious in adult females. However, in adult female leopard geckos (Eublepharis macularius), testosterone induces hemipene growth. We investigated whether these structures develop de novo in adulthood or are histologically present as rudimentary structures in the female leopard gecko. We also investigated the extent of sexual dimorphisms and plasticity in the associated neuromuscular components. To do this, we compared copulatory morphology (sizes of hemipenes, RPM and TPN muscle fibers, and associated motoneurons, as well as motoneuron and RPM fiber number) in adult females treated with testosterone, control females, and control males. All of the geckos possessed hemipenes, RPMs and TPNs, but these structures were indeed vestigial in control females. Testosterone induced striking increases in hemipene and copulatory muscle fiber size in females, but not to levels equivalent to control males. In parallel, males with increased levels of androgenic activity had larger hemipenes, suggesting naturally occurring steroid-induced plasticity. Copulatory motoneurons were not sexually dimorphic in size or number, and these measures did not respond to testosterone. The data demonstrate that the copulatory system of leopard geckos, in which gonadal sex is determined by egg incubation temperature, differs from that of many species (both reptilian and mammalian) with genotypic sex determination. Indeed, the system is remarkable in that adult females have normally occurring intersex characteristics and they exhibit substantial steroid-induced morphological plasticity in adulthood. [Copyright &y& Elsevier]

Thymus vulgaris is a gynodioecious species (in which females and hermaphrodites coexist) with a highly variable frequency of females among natural populations (5-95%) and a high average female frequency (60%). Sex determination involves both cytoplasmic genes responsible for male sterility, i.e. the female phenotype, and specific nuclear factors responsible for the restoration of male fertility, and thus a hermaphrodite phenotype. In this study, molecular markers of the mitochondrial genome have been used to quantify the cytoplasmic diversity in 11 clumps of individuals observed in four recently founded populations. The very low diversity within patches in conjunction with the strong diversity among patches strongly suggests that clumps of individuals are the result of single matrilinear families. In clumps that contain mainly females, all the analysed females showed the same cytoplasmic pattern. This pattern differed from that shown by neighbouring hermaphrodites, indicating that the determination of sex is locally cytoplasmic. A comparison of genetic diversity before and after fire in one population showed that disturbances may cause a reduction in genetic diversity and a concurrent induction of local cytoplasmic determination of sex. Such cytoplasmic determination of sex in colonizing populations, together with the greater seed set of females, may largely improve the colonizing ability of the species. [ABSTRACT FROM AUTHOR]

Talks about several issues concerning hermaphrodites. Emergence of intersex political activism; Discussion on the phenomenon of intersexuality; Information on African clitorectomy and intersex genital mutilation.

Patella ferruginea is a highly endangered species and the knowledge of its reproductive strategy is essential for suitable management and conservation. In this context, its strategy remained unclear and several authors argued that the species could be gonochorist. The evidence of length specific sex ratios in the sense of protandrous strategy has been confirmed by direct observation of sex change in the species. [ABSTRACT FROM AUTHOR]

The sex-determining region on the Y chromosome (SRY) gene guides male sexual development. However, individuals with sex reversal syndrome (46,XX males and 46,XX true hermaphrodites) lack the SRY gene and yet can still develop testes. We present 2 siblings with XX true hermaphroditism. Most cases of sex reversal syndrome are sporadic; however, reports have been published of familial occurrence, suggesting that 46,XX maleness and 46,XX true hermaphroditism are actually different manifestations of the same disorder of gonadal development, likely an autosomal dominant mutation with variable penetrance or an X-linked mutation. [Copyright &y& Elsevier]

Objective: To describe two unrelated Thai patients with suspected 5α-reductase type 2 deficiency and perform mutation analysis of the SRD5A2 gene. Design: Case report. Setting: A pediatric endocrinology clinic at a university hospital. Patient(s): Two unrelated patients with 46,XY karyotype, born with ambiguous genitalia, were studied. One was reared as a boy and the other was reared as a girl. Intervention(s): The entire coding regions of the SRD5A2 gene were assessed by polymerase chain reaction (PCR) and sequencing analysis. Main Outcome Measure(s): Molecular characterization of the SRD5A2 gene. Result(s): Four different pathogenic mutations (three missense and one nonsense) were identified. These were located at exon 1 (p.Q6X and p.L20P), exon 3 (p.G183S), and exon 4 (p.G203S). The T>C transition (c.59T>C) resulting in a leucine-to-proline substitution at codon 20 (p.L20P) has not been previously described and was not detected in 100 unaffected, ethnic-matched control chromosomes. In addition, p.G183S, previously identified only among patients from mixed African–European ancestry and in the Dominican Republic, was also detected in a Thai patient. Conclusion(s): This study demonstrates that the SRD5A2 gene is responsible for 5α-reductase type 2 deficiency across different populations and emphasizes the important role of genetic testing for the definite diagnosis and genetic counseling before gender assignment or any surgical intervention. [Copyright &y& Elsevier]

This article presents a study which aims to examine the occurrence of intersex and ovotestis in wild populations of a fish known as roach in rivers in Great Britain that are downstream from wastewater treatment plants. It shows that the sensitive period for feminization of the reproductive duct may occur earlier than previously thought, and raises new questions about the conditions that lead to actual germ cell disruption. The authors suggest possible explanations that need further study, one is that ovotestis is induced only by effluents with greater levels of estrogenic chemicals than those used in the study. The researchers evaluated the effluents for content of two chemicals previously implicated in causing intersex and found that these levels were similar to concentrations reported in wastewater effluents in Great Britain. They emphasize that chemical content and interactions ideally should be taken into account when trying to determine the conditions that lead to sexual effects.