There have been considerable advances concerning understanding of the early and later stages of ovarian development; a number of genes have been implicated and their mutations have been associated with developmental abnormalities. The most important genes controlling the initial phase of gonadal development, identical in females and males, are Wilms' tumor suppressor 1 (WT1) and steroidogenic factor 1 (SF1). Four genes are likely to be involved in the subsequent stages of ovarian development (WNT4, DAX1, FOXL2 and RSPO1), but none is yet proven to be the ovarian determining factor. changes in nomenclature and classification were recently proposed in order to incorporate genetic advances and substitute gender-based diagnostic labels in terminology. The term "disorders of sex development" (DsD) is proposed to substitute the previous term "intersex disorders". Three main categories have been used to describe DsD in the 46,XX individual: 1) disorders of gonadal (ovarian) development: ovotesticular DsD, previously named true hermaphroditism, testicular DsD, previously named XX males, and gonadal dysgenesis; 2) disorders related to androgen excess (congenital adrenal hyperplasia, aromatase deficiency and P450 oxidoreductase deficiency); and 3) other rare disorders. In this mini-review, recent advances concerning development of the genital system in 46,XX individuals and related abnormalities are discussed. basic embryology of the ovary and molecular pathways determining ovarian development are reviewed, focusing on mutations disrupting normal ovarian development. Disorders of sex development according to the revised nomenclature and classification in 46,XX individuals are summarized, including genetic progress in the field.
Denys-Drash and Frasier syndromes are rare human disorders that associate nephropathy with gonadal and genital abnormalities. In DDS there is a predisposition to Wilms' tumor. Heterozygous point mutations in the Wilms' tumor, type1 gene (WT1), particularly those altering the zinc finger (ZF) encoding exons, have been reported in most DDS patients, while mutations in intron 9 of the same gene cause FS. This paper describes two cases of DDS, one FS and one patient with Wilm's tumor and intersex genitalia, in which mutations were searched by sequencing the exons 8 and 9 of WT1 gene. Patient 1 carried a missense point mutation in exon 8 (ZF2), converting a CGA-Arg codon to a TGA-stop codon. Patient 2 presented a single nucleotide deletion within exon 9 (ZF3) introducing a premature chain termination at codon 398. Patients 3 and 4 had a C-->T transition at position +4 of the second alternative splice donor site of exon 9 (this mutation was detected in peripheral blood and in tumor derived DNA of patient 3). However, patient 3 had previously developed a Wilms' tumor. This is the first case of Wilms' tumor development in a phenotypically and genetically confirmed case of FS.
Background/Aims: Type 1 diabetes (T1DM) is associated with gastric autoimmunity, which is characterized by the presence of parietal cell antibodies (APCA). We investigated gastric autoimmunity prevalence in T1DM children, its manifestations, determinants and association with thyroid gland (anti-Tg, anti-TPO) and pancreatic β-cell autoimmunity (anti-GAD) at baseline and 4 years later. Methods: The initial cohort (D1) included 97 children with T1DM. At follow-up after 4 years (D2), 84.5% of participants were evaluated. We assessed APCA, anti-Tg, anti-TPO, and anti-GAD presence, as well as symptoms of gastritis. APCA-positive patients were evaluated with gastrin, B12, ferritin levels and were submitted to gastroscopy. Results: Thyroid antibody positivity was increased among the APCA-positive patients. Four years later, among initially APCA-positive patients, 2/6 became APCA negative, while 4/6 developed high titers of APCA. On gastroscopy, 2 patients had chronic hypertrophic gastritis and one Helicobacter pylori gastritis. Conclusions: Gastric autoimmunity was associated with thyroid autoimmunity and anti-GAD persistence. After 4 years, the majority of APCA-positive patients developed high titers of APCA and mild symptoms of gastritis. Thus, patients with T1DM, and in particular those with thyroid and/or pancreatic autoimmunity, should have periodic autoantibody screening for the early diagnosis and follow-up of gastric autoimmunity.
Background/Aims: Treatment with thyroxine in children with chronic autoimmune thyroiditis (AT) is controversial. The aim of this study is to investigate, by using thyroid ultrasonography, whether thyroxine influences thyroid volume in non-goitrous euthyroid children with AT. Methods: We studied 50 euthyroid non-goitrous children and adolescents with AT for 2 years by thyroid function tests and ultrasonography; 25 were randomized to receive thyroxine and 25 did not receive treatment. Median (IQR) age was 12.1 (11.1–13.2) years. Results: At baseline there was no difference in thyroid volume SDS between the two groups (treatment group 1.1 (0.7–1.5) and controls 0.9 (0.4–1.4), respectively). After 2 years the treatment group had lower thyroid volume SDS compared to the controls (0.6 (0.3–1.0) vs. 2.0 (1.1–2.3), p = 0.001). One child of the treatment group and 12 of the control group developed goiter. Two control children developed subclinical hypothyroidism. Within the treatment group, thyroid volume SDS was lower after 2 years of treatment (p = 0.002). Within the control group, thyroid volume SDS and TSH levels increased after 2 years of follow-up (p = 0.016, 1.9 (1.5–2.8) vs. 3.2 (2.4–4.4) mIU/ml, p = 0.006, respectively). Conclusions: Treatment with thyroxine reduces thyroid volume in non-goitrous euthyroid children with AT and may prevent goiter development.
Childhood obesity is a common and complex problem that may persist in adulthood. It may present as a component of genetic syndromes associated with dysmorphic features, developmental abnormalities, mental retardation and/or learning disabilities and often neuroendocrine dysfunction. Although the chromosomal abnormalities of these rare syndromes are already known, the specific genetic and pathophysiological mechanisms leading to the distinct phenotypes and obesity still remain unclarified. New exciting genetic pathways contributing to syndrome phenotype and leading to obesity have recently been identified. Prader-Willi syndrome is caused by loss of expression of the C/D box HBII-84 cluster of snoRNAs. Dysfunction of the primary cilium, thought to have important signalling functions, may contribute to disease phenotype and obesity in Bardet-Biedl, Alstrom and Carpenter syndromes. In this mini-review current knowledge of clinical and genetic characteristics is summarized as well as the pathogenesis of these syndromes with special emphasis on the pathogenesis of obesity.
Type 1 diabetes mellitus (T1DM) is characterized by selective autoimmune destruction of pancreatic b-cells, resulting in insulin deficiency. Associated autoimmune disorders, such as celiac disease, autoimmune thyroiditis, and gastritis, can coexist in patients with T1DM. These disorders are characterized by the presence of antibodies against tissue transglutaminase (anti-tTG-IgA), thyroglobulin, and thyroid peroxidase (anti-TG, anti-TPO), as well as antibodies against gastric parietal cells. Children with T1DM may also develop organ-specific multiple autoimmunity, with the coexistence of one or more autoimmune disorders. Furthermore, there is a lot of controversy regarding the role of thyroid autoimmunity in the pathogenesis of thyroid cancer. We present a child with T1DM and multiple autoimmunity including autoimmune Hashimoto's thyroiditis (HT), who developed thyroid cancer. The literature on the prevalence of associated autoimmunity in children with T1DM and the prevalence, pathogenesis, and timely diagnosis of thyroid cancer among patients with HT is also reviewed.
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