| Background:Hermaphroditism is a rare form of urogenital diseases. In recent years, with the improvement of clinical diagnosis and the enhancement of people's awareness of visits, the number of patients and accuracy rate of diagnosis gradually rise. Therefore, hermaphroditism is taken more and more seriously. Nevertheless, because of complex pathogenesis of hermaphroditism, the classification is confused. There has been more difficulty in clinical diagnosis, especially in male pseudohermaphroditism diagnosis.Male pseudohermaphroditism can be largely divided into different types according to etiology: 1,gonadotropin sexual function decline; 2,testosterone synthesis defect; 3,androgen receptor insensitivity syndrome; 4,5-a reductase deficiency; 5,Mullerian Duct Syndrome forever; 6,gonadal dysgenesis; 7,46XY feminization syndrome, etc. If further subdivided, there can be more types. Because of limited understanding of this disease, there are difficulties in diagnose, which leads to the blindness of treatment. Currently, some people argue that early diagnosis and comprehensive treatment are useful for treatment of some types of male pseudohermaphroditism. It not only reduces the financial burden of patients due to pain and trauma of surgery, but more importantly, protects patients against psychological influence to the greatest degree.The auxetic process of male reproductive system and the development of secondary sexual characteristics are considerably complex. Undifferentiated gonad in human is bipotential. SRY is a sex-determining gene in short arm of Y chromosome which induces bipotential gonads to testis. It is also the initiating factor in male development. Studies have shown that sex is not completely determined by the SRY gene whose absolute significance of testicular is questioned. Examining SRY gene could contribute to clarify the effect on clinical diagnosis. The development of testis is not only associated with upstream factors but also multiple roles of cytokines secreted by testis. Leydig and Sertoli cell of testis produces two hormones respectively, Müllerian-inhibiting substance (MIS) and testosterone. Testosterone can basically represent the function of testis, but it can not induce the development of masculinity, the male reproductive tract, secondary sexual characteristics. The physiological effects of MIS have been paid more attention. The main effect of MIS is to suppress mullerian duct developing to oviduct, uterus and supravaginal portion. So the dysfunction of MIS will lead to the hermaphroditism. We planed to examine the testis sensitivity of SRY gene, the expression of MIS, T in serum of male hermaphroditism in order to disclose the effect on the diagnosis of male hermaphroditism. The genes of MIS, SRY,T play important role on sex determine, so we detected the expression of MIS, T, SRY gene in the patients who have been diagnosised as male pseudohermaphroditism and explored their roles in disease diagnosis.Androgen insensitivity syndrome (AIS) which is the more common type of male pseudohermaphroditism, is divided into complete androgen insensitivity syndrome(CAIS) and incomplete androgen insensitivity syndrome (IAIS). AIS,the X-linked recessive genetic disease, is the mutation of androgen receptor gene in the X chromosome and the defect of androgen receptor of the cell membrane , resulting in androgen insensitivity. The study on etiology of AIS has been made great progress, and the possible pathogenic mutations have been reported, however, the exact mechanism of AIS is not clear. We examined the expression of androgen receptor in patients from small family constellation and tested the possible mutant gene to provide valuable evidences at the molecular level for the disease diagnosis.Objectives:To clarify the effect of three indicators (MIS, T, SRY) in the diagnosis of male pseudohermaphroditism and the relation between them for clinical treatment for providing more evidence to diagnosize male pseudohermaphroditism.,and to find the possible pathogenic mutant genes by examining the expression of androgen receptor in patients from small family constellation.Methods:Collect the fasting blood of patients (male pseudohermaphroditism) and normal people (non genital disease). After centrifugation, the supernatant (serum) is respectively placed into EP tube for testing MIS, T and the EDTA anticoagulant tube for genomic DNA.1. Extract DNA samples for testing karyotype and use PCR for testing SRY gene.2. Detection of expression of T and MIS by double antibody sandwich enzyme-linked immunosorbent assay (ELISA) and analysis the results, discussion for the meaning and relation between SRY, T, MIS and the diagnosis of male pseudohermaphroditism.3. Application of gene sequencing technique on DNA extracted from two patients suffering from complete androgen insensitivity syndrome, to find the possible gene mutation.Results:1. The level of MIS in patient group is significantly increase, compared to control group (p<0.05).2. The level of T in patient group is higer than that in contron group, but there is not significant difference (p>0.05).3. In patient group, five subjectes were postive, two subjectes were negative. In control group, seven cases were postive. All subjects have testes. The sensitivity for the diagnosis of testis was 92.8% (13/14).4. AR gene existing in a missense mutation exon 8 (from Arg to Glu) has been identified in patients with complete androgen insensitivity syndrome.Conclusions:1. MIS plays an important role in the diagnosis of male pseudohermaphroditism. Patients with high levels of MIS may suffer from male pseudohermaphroditism. Although the expression of T in the diagnosis has little significance, it is useful for typing and evaluating on the effect of treatment.2. SRY gene can not be considered as the only indicator evaluating the function and status of testis.3. There is basic radical permutation (from G to C) at 2615 in exon 8, resulting in the missense mutation from Arginine to Threonine.
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