Clinical and Molecular Cytogenetic Characteristics of Five Cases with Isodicentric Y Chromosome

2021 ◽  
pp. 1-9
Author(s):  
María C. Manotas ◽  
Mary García-Acero ◽  
Daniel M. González ◽  
Olga M. Moreno ◽  
Fernando Suárez-Obando ◽  
...  

Isodicentric Y chromosome [idic(Y)] is one of the most common structural abnormalities of the Y chromosome and has been observed in patients with reproductive disorders and in patients with disorders of sexual development. Most idic(Y) chromosomes are found in mosaic form with a 45,X cell line. These chromosomes are highly unstable during mitosis due to the presence of 2 centromers, which explains their probable loss in early mitosis or mitosis of the embryo and therefore the presence of the 45,X line. It has been hypothesized that the proportion of 45,X cells in various tissues probably influences the phenotypic sex of individuals carrying an idic(Y) chromosome, ranging from infertile men, hypospadias, ambiguous genitalia, and Turner syndrome to sex reversal. In this article we present 5 cases of patients with idic(Y) referred for suspected disorder of sex development (DSD), 3 with a male assignment and 2 with a female assignment. All cases have variable clinical characteristics, which were assessed by the transdisciplinary group of Disorders of Sex Development of the Hospital Universitario San Ignacio, Bogotá, Colombia. Patients were analyzed by conventional and molecular cytogenetics using high-resolution G-band and FISH techniques. Our findings highlight the importance of cytogenetic studies in the diagnosis of DSD patients.

2020 ◽  
Vol 14 (2) ◽  
pp. 134-138
Author(s):  
Eva Jesmin ◽  
Fauzia Mohsin ◽  
Nurun Nahar Fatema Begum

Introduction: 46 XY disorders of sexual development (DSD) include a wide sphere of phenotypes which can be ambiguous male genitalia with or without hypospadias, unambiguous female genitalia or dysgenetic gonads or any combination of them. Management of these patients depends on the aetiology, age at presentation, gender orientation and advancement in feminization. Objectives: To assess the clinical, biochemical, radiological and chromosomal profile of the paediatric patients with suspected DSD attending a tertiary level healthcare centre and plan for appropriate management. Materials and Methods: This cross-sectional study was carried out among 30 cases of 46XY DSD attending the paediatric endocrine unit of Bangladesh Institute of Research and Rehabilitation in Diabetes Endocrine and Metabolic Disorders (BIRDEM) General Hospital from May 2016 to April 2017. Clinical, biochemical, radiological and chromosomal evaluations were done to identify the cause of DSD. Results: The mean age of the patients recruited in the study was 3.51 (±5.03) years ranging from 13 days old to 13 years old. Among these 30 patients, the chief complaint was ambiguous genitalia in 29 (96.7%) cases, 1 (3.3%) case with Micropenis and 1 (3.3%) case with absence of development of secondary sexual characteristics. The gender of rearing was male in 23 (76.7%) cases and rest as female. Among the patients 5 (16.67%) patients were diagnosed with PAIS, 5 (16.67%) patients with CAIS, 3 (10%) patients had a deficiency of 5αRD and gonadal dysgenesis was found in 5 (16.67%) patients. The corrective surgery was done in 5(16.67%) patients, 16 (53.3%) patients referred to surgeon for operative treatment and 7(23.3%) patients were prescribed to administer testosterone. Conclusions: The early presentation, correct identification of the cause and initiation of cause-based treatment can abate the physical and psychosocial complications and may support better gender orientation related adjustability. Journal of Armed Forces Medical College Bangladesh Vol.14 (2) 2018: 134-138


Author(s):  
Kazuhisa Akiba ◽  
Keiko Aso ◽  
Yukihiro Hasegawa ◽  
Maki Fukami

Abstract Objectives 5α-reductase type 2 deficiency due to biallelic SRD5A2 variants is a common form of 46,XY disorders of sex development. Case presentation A Chinese neonate presented with ambiguous genitalia. He carried a homozygous likely_pathogenic SRD5A2 variant (c.650C>A, p.A217E). His apparently nonconsanguineous parents were heterozygotes for the variant. The variant has previously been identified in two Chinese patients. Our patient carried 14.2 Mb loss-of-heterogeneity regions distributed in the genome. The SRD5A2 variant in this family was invariably coupled with two polymorphisms in exon 1 and intron 1. In the patient, blood testosterone (T)/5α-dihydrotestosterone (5αDHT) ratios were elevated before and during mini puberty, and were higher when measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS) than measured by conventional immune assays. Conclusions This study provides evidence for the founder effect of an SRD5A2 variant. Furthermore, our data indicate that there is a need to establish a new reference value for T/5αDHT ratios using LC-MS/MS.


2008 ◽  
Vol 11 (2) ◽  
pp. 51-58
Author(s):  
A Lungeanu ◽  
A Arghir ◽  
S Arps ◽  
G Cardos ◽  
N Dumitriu ◽  
...  

Chromosome Y Isodicentrics in two Cases with Ambiguous genitalia and Features of Turner SyndromeKaryotype investigations using classical cytogenetics, fluorescencein situhybridization (FISH) and polymerase chain reaction (PCR) techniques were used for the characterization of Y chromosome structural anomalies found in two patients with ambiguous genitalia and features of Turner syndrome. Both exhibited mosaic karyotypes of peripheral blood lymphocytes. The karyotype was 45, X[90]/ 46, X, idic(Y)(p11.3).ish idic(Y) (wcpY+, DXYS130++,SRY++,DYZ3++,DYZ1++, DYS224++)[10] in one case, and the karyotype was 45, X[65]/46, X, idic(Y) (q11).ish idic(Y)(SRY++, RP11-140H23-)[35] in the other case. Derivative Y chromosomes were different in shape and size and positive for the SRY gene, a common underlying element of ambiguous genitalia phenotypes. These results add new information concerning the role of Y chromosome structural abnormalities in sex determination pathway perturbation which are poorly understood, and highlight the importance of the sex chromosomes integrity for a normal sex phenotype development.


Author(s):  
David F.M. Thomas

The aetiology of disorders of sex development (DSD) is multifactorial and includes chromosomal defects, developmental abnormalities of the gonads, and defects of hormonal synthesis and expression. Infants born with ambiguous genitalia require urgent investigation because of the risk of hyponatraemia associated with congenital adrenal hyperplasia (CAH) and to permit an informed decision on gender assignment. CAH is the commonest form of DSD, accounting for around 80% of all infants born with ambiguous genitalia. Despite controversy regarding timing and consent, feminizing genitoplasty in early childhood remains the accepted management for girls with significant clitoromegaly. Surgical reconstruction for 46XY DSD is guided by several factors, notably the size of the phallus and gonadal phenotype. The majority of individuals with disorders of sex development will require ongoing specialist care and long-term multidisciplinary follow-up and support.


2019 ◽  
Vol 20 (20) ◽  
pp. 5017 ◽  
Author(s):  
Leendert H. J. Looijenga ◽  
Chia-Sui Kao ◽  
Muhammad T. Idrees

The risk of gonadal germ cell cancer (GGCC) is increased in selective subgroups, amongst others, defined patients with disorders of sex development (DSD). The increased risk is due to the presence of part of the Y chromosome, i.e., GonadoBlastoma on Y chromosome GBY region, as well as anatomical localization and degree of testicularization and maturation of the gonad. The latter specifically relates to the germ cells present being at risk when blocked in an embryonic stage of development. GGCC originates from either germ cell neoplasia in situ (testicular environment) or gonadoblastoma (ovarian-like environment). These precursors are characterized by presence of the markers OCT3/4 (POU5F1), SOX17, NANOG, as well as TSPY, and cKIT and its ligand KITLG. One of the aims is to stratify individuals with an increased risk based on other parameters than histological investigation of a gonadal biopsy. These might include evaluation of defined susceptibility alleles, as identified by Genome Wide Association Studies, and detailed evaluation of the molecular mechanism underlying the DSD in the individual patient, combined with DNA, mRNA, and microRNA profiling of liquid biopsies. This review will discuss the current opportunities as well as limitations of available knowledge in the context of predicting the risk of GGCC in individual patients.


2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Prisca Amolo ◽  
Paul Laigong ◽  
Anjumanara Omar ◽  
Stenvert Drop

Objective. The purpose of this study was to describe baseline data on etiological, clinical, laboratory, and management strategies in Kenyan children and adolescents with Disorders of Sex Development (DSD). Methods. This retrospective study included patients diagnosed with DSD who presented at ages 0–19 years from January 2008 to December 2015 at the Kenyatta National (KNH) and Gertrude’s Children’s (GCH) Hospitals. After conducting a search in the data registry, a structured data collection sheet was used for collection of demographic and clinical data. Data analysis involved description of the frequency of occurrence of various variables, such as etiologic diagnoses and patient characteristics. Results. Data from the records of 71 children and adolescents were reviewed at KNH (n = 57, 80.3%) and GCH (n = 14, 19.7%). The mean age at the time of diagnosis was 2.7 years with a median of 3 months. Thirty-nine (54.9%) children had karyotype testing done. The median age (IQR) of children with reported karyotypes and those without was 3.3 years (1.3–8.9) and 8.3 years (3.6–12.1), respectively (p=0.021). Based on karyotype analysis, 19 (48.7%) of karyotyped children had 46,XY DSD and 18 (46.2%) had 46,XX DSD. There were two (5.1%) children with sex chromosome DSD. Among the 71 patients, the most common presumed causes of DSD were ovotesticular DSD (14.1%) and CAH (11.3%). Majority (95.7%) of the patients presented with symptoms of DSD at birth. The most common presenting symptom was ambiguous genitalia, which was present in 66 (93.0%) patients either in isolation or in association with other symptoms. An ambiguous genitalia was initially observed by the patient’s mother in 51.6% of 62 cases despite the high rate (84.7%) of delivery in hospital. Seventeen (23.9%) of the cases had a gender reassignment at final diagnosis. A psychologist/psychiatrist or counselor was involved in the management of 23.9% of the patients. Conclusion. The commonest presumed cause of DSD was ovotesticular DSD in contrast to western studies, which found CAH to be more common. Investigation of DSD cases is expensive and needs to be supported. We would have liked to do molecular genetic analysis outside the country but financial challenges made it impossible. A network for detailed diagnostics in resource-limited countries would be highly desirable. There is a need to train health care workers and medical students for early diagnosis. Psychological evaluation should be carried out for all patients at diagnosis and support given for families.


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