China
Africa
Explore chapters and articles related to this topic
Surgical treatment of disorders of sexual development
Published in Mark Davenport, James D. Geiger, Nigel J. Hall, Steven S. Rothenberg, Operative Pediatric Surgery, 2020
Rafael V. Pieretti, Patricia K. Donahoe
Two practical screening criteria, gonadal symmetry or asymmetry and the presence of a Y chromosome, can be used to help in the early diagnosis of the infant as having one of the four DSD disorders. Probes for SRY can be used to sequence or genotype the SRY gene. Gonadal symmetry is determined by the position of one gonad relative to the other, either above or below the external inguinal ring. If both gonads are symmetrical, then a diffuse biochemical cause underlies the abnormality, as in 46,XX DSD female with excess androgens or in a 46,XY DSD male with diminished androgens, which are biochemical anomalies that influence both gonads equally. Asymmetry occurs in MGD and ovotesticular DSD (true hermaphroditism), which are chromosomal abnormalities in which a predominant testis descends and a predominant ovary remains above the external ring. The karyotype is always 46,XX in cases of 46,XX DSD (female pseudohermaphroditism with adrenogenital syndrome) and is most often (90%) the case in patients with ovotesticular DSD (true hermaphroditism). Patients with 46,XY DSD (male pseudohermaphroditism) or MGD always have a Y chromosome in their karyotype (see studies from MacLaughlin and Donahoe in 2004 and Donahoe and colleagues in 2005 in “Further Reading”).
Endocrinology and gonads
Published in Jagdish M. Gupta, John Beveridge, MCQs in Paediatrics, 2020
Jagdish M. Gupta, John Beveridge
11.31. Which of the following statements is/are true of sexual development in the fetus?Female genital development does not require gonads.The sry gene is necessary for the development of the testis.Testosterone is necessary for the development of vas deferens, epididymis and seminal vesicles.In the male, Miillarian ducts differentiate into vas deferens, epididymis and seminal vesicles.In the female, Miillarian ducts differentiate into Fallopian tubes, uterus and upper part of vagina.
Prenatal Diagnosis
Published in Victor A. Bernstam, Pocket Guide to GENE LEVEL DIAGNOSTICS in Clinical Practice, 2019
Genetic studies of XY females with gonadal dysgenesis, as well as of normal males, identified mutations within the SRY gene responsible for sex reversal in the affected individuals. Amplification of SRY sequences from the DNA of XY females or normal males by PCR revealed that although SRY is required for male sex determination, this is not the “ultimate” TDF gene. A specific DNA-binding activity encoded by SRY appears to be essential for sex determination.
Cytogenetic analysis of patients with primary amenorrhea in Eastern India
Published in Journal of Obstetrics and Gynaecology, 2018
Shaulee Ghosh, Sanchita Roy, Pritha Pal, Atreyee Dutta, Ajanta Halder
Interestingly, in our study male karyotype [46, XY] was found in three cases. These XY female cases had normal stature and structurally normal female external genitalia, vagina, uterus, and fallopian tubes. In these cases secondary sexual development did not occur at puberty and gonadotropins (follicle-stimulating hormone [FSH], luteinising hormone [LH]) were elevated and oestrogens decreased. SRY is the testis-determining factor (TDF) on the Y chromosome (Sinclair et al. 1990; Koopman et al. 1991) which initiates the bi-potential gonads to differentiate into the testis and in the absence of the expression from the SRY gene; the bi-potential gonads differentiate into inappropriate female gonads. Hormonal treatment is similar to that used for any patient with primary gonadal failure. An important clinical feature is the high risk of dysgerminoma or gonadoblastoma, which is approximately 20–30% without medical intervention necessitating gonads being extirpated in XY gonadal dysgenesis (Behtash and Karimi Zarchi 2007; Jorgensen et al. 2010). Successful pregnancies have been reported in 46, XY gender-reversed females (Dumic et al. 2008).
Molecular study and genotype–phenotype in Chinese female patients with 46, XY disorders of sex development
Published in Gynecological Endocrinology, 2021
Junke Xia, Jing Wu, Chen Chen, Zhenhua Zhao, Yanchuan Xie, Zhouxian Bai, Xiangdong Kong
The SRY gene (OMIM #480000) induces bipotential gonads to differentiate into testicles [2]. SRY mutation has been reported in females with 46, XY karyotype, known as Swyer syndrome [3,4]. Additionally, mutations in genes involved in gonadal determination, such as NR5A1, SOX9, and LHCGR, have been identified in patients with 46, XY DSDs [5–9]. Gene defects in the androgen receptor (AR) lead to androgen dysfunction in despite of normal androgen biosynthesis [10]. Numerous genes and hormones involved in the process have been identified, and gene mutations could lead to DSDs. Moreover, considering the overlap in clinical features among various genetic causes, determination of the specific etiology of 46, XY DSDs is often more challenging.
Is chronic pain as an autoimmune disease?
Published in Canadian Journal of Pain, 2022
All Y-linked genes are expressed, unlike X chromosome genes, from genes that are duplicated and hemizygous, except in cases of aneuploidy. Reconstruction across mammalian species based on evolution suggests that preservation of specific parts of the Y chromosome occurs randomly over time.64 It appears that the gene content of the Y chromosome has selectively become specialized to maintain the ancestral dosage of homologous XY gene pairs that act as key regulators of transcription, translation, and protein stability in a number of tissues. Several ancestral genes on the human Y chromosome seem to have survived, with four genes (HSFY, RBMY, SRY, and TSPY). These encoding isoforms have functionally diverged from their X-encoded homologs (HSFX, RBMX, SOX3, and TSPX) to ensure male reproductive development or gametogenesis.64 It appears that in mammals, the SRY gene is the main driver of male development. Several ubiquitously expressed ancestral genes exhibit subtle functional differences from their X-linked homologs. Eight of the regulators of transcriptional activity present in a number of human tissues, including DDX3X/Y, EIF1AX/Y, KDM5C/D, RPS4X/Y, TBL1X/Y, USP9X/Y, UTX/Y, and ZFX/Y, illustrate a biochemical sexual dimorphism that is directly linked to genetic differences between the X and Y chromosomes. Several of these genes (EIF1A, UTX) have been associated with chronic pain, as suggested earlier. Thus, the Y chromosome could have an underappreciated role in broader sex differences that influence processes other than testis determination and spermatogenesis that impact normal physiology as well as pathology.