Gonadoblastoma Y locus genes expressed in germ cells of individuals with dysgenetic gonads and a Y chromosome in their karyotypes include DDX3Y and TSPY.

STUDY QUESTION: Which Y genes mapped to the 'Gonadoblastoma Y (GBY)' locus on human Y chromosome are expressed in germ cells of individuals with some Differences of Sexual Development (DSD) and a Y chromosome in their karyotype (DSD-XY groups)? SUMMARY ANSWER: The GBY candidate genes DDX3Y and TSPY are expressed in the germ cells of DSD-XY patients from distinct etiologies: patients with mixed gonadal dysgenesis (MGD) and sex chromosome mosaics (45,X0/46,XY; 46,XX/46,XY); patients with complete androgen insensitivity (CAIS), patients with complete gonadal dysgenesis (CGD; e.g. Swyer syndrome). WHAT IS KNOWN ALREADY: A GBY locus was proposed to be present on the human Y chromosome because only DSD patients with a Y chromosome in their karyotype have a high-although variable-risk (up to 55%) for germ cell tumour development. GBY was mapped to the proximal part of the short and long Y arm. TSPY located in the proximal part of the short Y arm (Yp11.1) was found to be a strong GBY candidate gene. It is expressed in the germ cells of DSD-XY patients with distinct etiologies but also in foetal and pre-meiotic male spermatogonia. However, the GBY region extends to proximal Yq11 and therefore includes probably more than one candidate gene. STUDY DESIGN, SIZE, DURATION: Protein expression of the putative GBY candidate gene in proximal Yq11, DDX3Y, is compared with that of TSPY in serial gonadal tissue sections of 40 DSD-XY individuals from the three DSD patient groups (MGD, Complete Androgen Insensitivity Syndrome [CAIS], CGD) with and without displaying malignancy. Expression of OCT3/4 in the same tissue samples marks the rate of pluripotent germ cells. PARTICIPANTS/MATERIALS, SETTING, METHOD: A total of 145 DSD individuals were analysed for the Y chromosome to select the DSD-XY subgroup. PCR multiplex assays with Y gene specific marker set score for putative microdeletions in GBY Locus. Immunohistochemical experiments with specific antisera mark expression of the GBY candidate proteins, DDX3Y, TSPY, in serial sections of the gonadal tissue samples; OCT3/4 expression analyses in parallel reveal the pluripotent germ cell fraction. MAIN RESULTS AND THE ROLE OF CHANCE: Similar DDX3Y and TSPY protein expression patterns were found in the germ cells of DSD-XY patients from each subgroup, independent of age. In CAIS patients OCT3/4 expression was often found only in a fraction of these germ cells. This suggest that GBY candidate proteins are also expressed in the non-malignant germ cells of DSD-XY individuals like in male spermatogonia. LIMITATIONS, REASONS FOR CAUTION: Variation of the expression profiles of GBY candidate genes in the germ cells of some DSD-XY individuals suggests distinct transcriptional and translational control mechanisms which are functioning during expression of these Y genes in the DSD-XY germ cells. Their proposed GBY tumour susceptibility function to transform these germ cells to pre-malignant GB/Germ Cell Neoplasia in Situ (GB/GCNIS) cells seems therefore to be limited and depending on their state of pluripotency. WIDER IMPLICATIONS OF THE FINDINGS: These experimental findings are of general importance for each individual identified in the clinic with DSD and a Y chromosome in the karyotype. To judge their risk of germ cell tumour development, OCT3/4 expression analyses on their gonadal tissue section is mandatory to reveal the fraction of germ cells still being pluripotent. Comparative expression analysis of the GBY candidate genes can be helpful to reveal the fraction of germ cells with genetically still activated Y chromosomes contributing to further development of malignancy if at high expression level. STUDY FUNDING/COMPETING INTEREST(S): This research project was supported by a grant (01GM0627) from the BMBF (Bundesministerium für Bildung und Forschung), Germany to P.H.V. and B.B. The authors have no competing interests.

Pseudoautosomal inheritance of Léri-Weill syndrome: what does it mean?

The short stature homeobox (SHOX) gene is located in the pseudoautosomal region 1 of both sex chromosomes. Haploinsufficiency of SHOX leads to different phenotypes ranging from isolated short stature to Léri-Weill syndrome characterized by short stature, mesomelia and Madelung deformity. We describe a family with a SHOX deletion originally located on the Y chromosome and transmitted from father to daughter by crossover during meiosis. The male index patient presented with short stature, mesomelia and mild Madelung deformity. His father had a normal height but slightly disproportionate short legs. The sister of the index patient presented with marked Madelung deformity and normal height. A deletion of the SHOX gene was identified in the male index patient, his father and his sister. Metaphase fluorescence in situ hybridization (FISH) analyses showed a deletion of the SHOX gene on the Y chromosomes of the index patient and his father, and on the X chromosome of his sister, indicating that a meiotic crossover of the SHOX gene region between the X and Y chromosomes had occurred. The pseudoautosomal region 1 is a known recombination 'hot spot' in male meiosis. Published genetic maps indicate high recombination frequency of ∼40% for SHOX in male meiosis leading to pseudoautosomal inheritance.

Congenital disorder of glycosylation IId (CDG-IId) -- a new entity: clinical presentation with Dandy-Walker malformation and myopathy.

A 1.5-year-old boy with macrocephaly due to a Dandy-Walker malformation presented with progressive hydrocephalus, extensive muscular hypotonia, transient cholestatic syndrome, extensive coagulation abnormalities and elevated creatine kinase indicating myopathy. Diagnostic work-up indicated a congenital disorder of glycosylation (CDG, formerly carbohydrate deficient glycoprotein syndrome). The serum transferrin pattern obtained by automated isoelectric focusing (IEF) showed an hitherto unreported pattern with strongly elevated tri-, di-, mono- and asialotransferrin bands, increasing in this order together with markedly decreased tetrasialotransferrin. Investigation of two additional glycoproteins, alpha(1)-antitrypsin and alpha(1)-antichymotrypsin, confirmed a generalised defect of glycosylation. All known glycosylation defects could be ruled out by enzymatic analyses in either leukocytes or fibroblasts or by the results obtained by IEF. SDS-electrophoresis demonstrated a marked difference in the molecular weight of transferrin, suggesting the lack of parts or of all oligosaccharide chains. The defect could be delineated to a deficiency of beta-1,4-galactosyltransferase (E.C.2.4.1.38) due to a homozygous insertion (1031 - 1032 insC). Details of the biochemical and molecular findings will be described elsewhere.

Phaeochromocytoma associated with a de novo VHL mutation as form fruste of von Hippel-Lindau disease.

UNLABELLED: Phaeochromocytomas usually occur sporadically but may be associated with dominant inherited cancer syndromes such as multiple endocrine neoplasia type 2 (MEN 2), von Hippel-Lindau disease (VHL) and type 1 neurofibromatosis. We report on a boy presenting at age 8 years with an isolated benign phaeochromocytoma of the left adrenal. Three years later a second adrenal phaeochromocytoma was diagnosed on the right side and removed. His family history was negative. Genetic analysis did not show a mutation in the MEN 2 susceptible proto-oncogene rearranged during transfection; however, we found a germline missense mutation in the VHL gene (nucleotide 695 G to A transversion) which has been described only twice before in the literature. Both parents had normal (wild type) VHL copies indicating that our patient had a de novo germline VHL mutation. Careful clinical evaluation of the patient at 18 years did not reveal any other manifestations of VHL disease. CONCLUSION: Carriers of von Hippel-Lindau germline mutations can present with a form fruste of von Hippel-Lindau disease presenting initially with unilateral phaeochromocytoma and therefore mutation analysis should be carried out.

Disseminated choriocarcinoma in infancy is curable by chemotherapy and delayed tumour resection.

Infantile choriocarcinoma has a poor prognosis with only 2 surviving children reported in the literature. 2 additional successfully treated children are presented. 2 infants (age 3 and 4 months at diagnosis) suffering from rapidly progressive choriocarcinoma with widespread haematogenous metastases involving the liver were treated according to the cooperative germ cell tumour treatment protocol (MAKEI 96) of the German Society of Pediatric Oncology and Hematology (GPOH). PEI-chemotherapy (cisplatin, etoposide, ifosfamide; no ifosfamide before the age of 4 months) was combined with delayed tumour resection. Treatment resulted in sustained remission in both children (event-free survival 42 and 40 months). Interphase fluorescent in situ hybridisation (FISH) analysis of the paraffin-embedded tumour sample from case one revealed four to eight copies of chromosomes X, 1 and 17 and two Y chromosomes. Hybridisation with sub-telomere and centromere specific probes for chromosome 1 displayed an imbalance between the short and long arms of chromosome 1. In the tumour cells from case 2, only a polysomy of chromosome X could be proven, other aberrations were not analysed in this case for technical reasons.

A novel mutation in the thiamine responsive megaloblastic anaemia gene SLC19A2 in a patient with deficiency of respiratory chain complex I.

The thiamine transporter gene SLC19A2 was recently found to be mutated in thiamine responsive megaloblastic anaemia with diabetes and deafness (TRMA, Rogers syndrome), an early onset autosomal recessive disorder. We now report a novel G1074A transition mutation in exon 4 of the SLC19A2 gene, predicting a Trp358 to ter change, in a girl with consanguineous parents. In addition to the typical triad of Rogers syndrome, the girl presented with short stature, hepatosplenomegaly, retinal degeneration, and a brain MRI lesion. Both muscle and skin biopsies were obtained before high dose thiamine supplementation. While no mitochondrial abnormalities were seen on morphological examination of muscle, biochemical analysis showed a severe deficiency of pyruvate dehydrogenase and complex I of the respiratory chain. In the patient's fibroblasts, the supplementation with high doses of thiamine resulted in restoration of complex I activity. In conclusion, we provide evidence that thiamine deficiency affects complex I activity. The clinical features of TRMA, resembling in part those found in typical mitochondrial disorders with complex I deficiency, may be caused by a secondary defect in mitochondrial energy production.

Characterization of eleven novel mutations (M45L, R119H, 544delG, G145V, H154Y, C184Y, D289V, 862+5A, 1172delC, R411X, E459K) in the tissue-nonspecific alkaline phosphatase (TNSALP) gene in patients with severe hypophosphatasia. Mutations in brief no. 217. Online.

Hypophosphatasia is a rare inherited disorder characterized by defective bone mineralization and deficiency of serum and tissue liver/ bone/kidney tissue alkaline phosphatase (L/B/K ALP) activity. We report the characterization of tissue-nonspecific alkaline phosphatase (TNSALP) gene mutations in a series of 9 families affected by severe hypophosphatasia. Fourteen distinct mutations were found, 3 of which were previously reported in the North American or Japanese populations. Seven of the 11 new mutations were missense mutations (M45L, R119H, G145V, C184Y and H154Y, D289V, E459K), the four others were 2 single nucleotide deletions (544delG and 1172delC), a mutation affecting donor splice site (862 + 5A) and a nonsense mutation (R411X).

Functioning thoracic paraganglioma: association with Von Hippel-Lindau syndrome.

Functioning thoracic paraganglioma (pheochromocytoma) is unusual and therefore suggestive of a pathogenesis distinct from that of sporadic adrenal pheochromocytoma. To determine whether the pheochromocytoma-associated syndromes Von Hippel-Lindau disease (VHL) and multiple endocrine neoplasia type 2 (MEN 2) play a role in the development of thoracic functioning paragangliomas, germline DNA from five unselected patients with this rare tumor was analyzed for mutations in the genes that predispose to VHL and MEN 2. Genetic investigations and further clinical data revealed that three had VHL, with two different germline mutations of the vhl gene, but no individual was affected by MEN 2. Two of the three patients with VHL did not show any additional VHL-associated lesions. This result suggests that VHL should be considered in the differential diagnosis of thoracic pheochromocytoma, as such a diagnosis carries further important implications for the patient and family. Conversely, in patients suspected of a catecholamine-secreting tumor and known VHL, thoracic localization should be considered if an adrenal pheochromocytoma cannot be detected.

[Hypophyseal microprolactinoma as a cause of delayed puberty]. / Hypophysäres Mikroprolaktinom als Ursache einer Pubertätsverzögerung.

Hyperprolactinaemic hypogonadism in adults is a well defined disease with clinical symptoms like ovarian hypofunction or amenorrhea and galactorrhea in females and loss of sexual activity in males. In pediatrics this special form of hypogonadism is almost unknown. Typical manifestation is delay in puberty or pubertal arrest. We describe a 20 year old man with signs of delay of puberty. Endocrinological work-up revealed a decreased pulse frequency of luteinizing hormone resulting in pathologically low testosterone concentrations. The final cause of hypothalamic hypogonadism was a prolactin producing pituitary microadenoma. During long-term treatment with a dopaminergic drug the elevated prolactin levels decreased to the normal range and testicular function normalized as shown by growth of the testes and increasing testosterone levels.

[Iodine excretion and dietary iodine supply in newborn infants in iodine-deficient regions of West Germany]. / Jodausscheidung und alimentäre Jodversorgung bei Neugeborenen in Jodmangelgebieten der Bundesrepublik.

Urinary iodine excretion was measured on the fifth day of life in 461 neonates from nine different towns in the Federal Republic of Germany. There was a progressive fall in levels from north to south, with highest values in Hamburg (2.9 micrograms/dl) and lowest in Freiburg (1.2 micrograms/dl). All levels were lower than those of neonates in other countries in which iodine is added to salt: Stockholm (61 neonates) 9.6 micrograms/dl, Zurich (63) 4.75 micrograms/dl. Iodine analysis of mothers in G ottingen on the fifth day post-partum indicated that iodine excretion in urine of mothers with goitre (51 cases) was significantly lower than in a control group without goitre (38): 17.6 compared with 30.0 micrograms/g creatinine, and the iodine content of breast milk in the goitre group was significantly lower than that of the control group (1.75 compared with 2.5 micrograms/dl). Iodine content in artificial infant milk preparations was of a similar range. These results indicate that iodine supply during the neonatal period in the Federal Republic of Germany is very low; they support the demand for general iodine-salt prophylaxis.

Incidence of iodine contamination in neonatal transient hyperthyrotropinemia.

Transient hyperthyrotropinemia and/or hypothyroidism have been found in many newborn infants during thyroid screening programs. In Europe the most likely causes are iodine deficiency and iodine overload. Because of the high incidence of transient hyperthyrotropinemia in Berlin we measured iodine concentrations in casual urine samples of newborns with TSH elevations. Urine and blood samples were collected on the 5th day of life. In the prospective study 99 out of 9320 newborns (1.06%) displayed TSH concentrations ranging from 20 to 152 microU/ml. All infants had normal TSH levels during a control examination. The urinary iodine concentrations were significantly elevated in 76 out of the 99 newborns. Most of the patients were born in obstetric departments where iodine-containing antiseptic agents were routinely used for disinfection during labor. The use of iodine-containing antiseptic agents not only results in unnecessary control determinations for the thyroid screening program but also causes an undesirable metabolic situation that may be a potential hazard for the development of the central nervous system.

Iodine-induced hypothyroidism and goiter following lipiodolTM lymphography.

Hypothyroid goiter is a rare but well recognized complication following long term administration of iodine containing expectorants and disinfectants in children. Only few reports exist on iodine-induced hypothyroidism after a single injection of the iodized radiopaque dye Lipiodol. A 15-year-old boy with previously normal thyroid function is described who developed hypothyroid goiter within six weeks following bipedal lymphography. Urinary iodine excretion was extremely elevated up to 18 mg/day while serum concentrations of total thyroxine were below the euthyroid range and thyrotropin levels were elevated. After oral L-thyroxine treatment the goiter disappeared. Thyroid function remained normal when treatment was discontinued after five months although iodine excretion was still 50 times higher (2.5 mg/day) than in normal age matched children. The observed alterations of the thyroid gland were caused by a long lasting Wolff-Chaikoff effect with a delayed adaptation to high iodide concentrations.

Influence of prenatal exposure to diethylstilbestrol on estrogen and progestin binding proteins in uteri and dimethylbenzanthracene- induced mammary tumors of the rat.

Various characteristics of steroid binding proteins from mammary tumors and uteri of rats exposed prenatally to diethylstilbestrol (DES) were examined. Pregnant rats were treated with no hormone (group A) or with a total dose of 1.2 micrograms DES during the second (group B) or third (group C) trimester of gestation. Female offspring received 7,12-dimethylbenz[a]anthracene (DMBA) at d 50 +/- 1. Animals with large mammary tumors were subjected to bilateral ovariectomy. Seven months after carcinogen treatment, the experiment was terminated. High-affinity binding sites for [3H] estradiol-17 beta and [3H]R5020 were found in all mammary tumors assayed. On sucrose gradients of low ionic strength both 8S and 4S forms of the estrogen receptor were identified in mammary tumors, regardless of prenatal treatment. In addition, progestin receptors sedimenting at 4S were identified in these tumors. However, the 7-8S form of the progestin receptor was found only in tumors from intact animals. Levels of progestin receptors were diminished after ovariectomy, both in mammary tumors and in uteri; ovariectomy also resulted in a significant reduction in uterine wet weight in the hormone exposure groups, as expected. Unlike groups A and B, rats exposed to DES during the third trimester had uterine progestin binding capacities and uterine wet weights that did not decrease proportionally ater ovariectomy. Furthermore, progestin binding capacities in mammary tumors from group C ovariectomized rats were higher than those in the other two groups. In intact rats from group C, cytosol from mammary tumors also had elevated levels of progestin binding; however, no differences in progestin binding were observed in the uteri from these animals. Small differences in estrogen binding capacities in tumor tissues were observed among the three groups; uterine estrogen binding capacities did not vary significantly. Prenatal exposure to DES during the third trimester appeared related to persistent biochemical alterations in rat mammary tumors and uteri; earlier exposure did not have this effect.

14C-labeled proteins as markers for gradient analysis of steroid-hormone receptors.

Two useful [14C]marker proteins--[14C]human serum albumin (4.6S) and [14C]glucose oxidase (7.9S)--can be simply prepared. Both may be used as molecular-mass standards in polyacrylamide gel electrophoresis as sucrose density-gradient centrifugation. The utility of these markers for estrogen receptor studies was investigated under a variety of conditions, to ensure that they do not interfere with current assay procedures. Their use as internal markers allows more samples to be analyzed per rotor, a significant factor because each centrifugation run requires 16 h and two bucket spaces for each sample assayed; improves accuracy and overall quality control by eliminating any problems resulting from variations among individual gradients; and facilitates evaluation of changes in gradient profiles, which may provide clinically and biochemically relevant information concerning the microheterogeneity of estrogen receptors.

Preparation of cytosol for steroid receptor determinations with the Beckman "Airfuge".

Preparation of cytosols from several estrogen target organs was compared, with use of the Beckman Airfuge and a preparative ultracentrifuge. The specific estrogen-binding capacities of cytosols prepared with these instruments were indistinguishable. Similarly, the sedimentation profiles of estrogen-receptor species as determined by sucrose gradient centrifugation were identical. We conclude that the Airfuge provides a rapid, accurate, and inexpensive means of preparing cytosols for measurements of steroid receptors in the clinical laboratory.

[Hypothyroid, iodine-deficient goitre in neonates (author's transl)]. / Die hypothyreote Jodmangelstruma im Neugeborenenalter. Häufigkeit, endokrinologische Besonderheiten und Therapie.

Within one year 1750 mature neonates were examined for congenital hypothyroidism. The region of Göttingen is known to be an iodine-deficient one. Sixteen goitrous, hypothyroid neonates with a low total thyroxine, and raised serum TSH concentration were first diagnosed through this screening programme. As a result of the intra-uterine iodine deficiency, serum triiodothyronine concentration was elevated while urinary iodine excretion was reduced compared with euthyroid neonates. During iodine treatment the size of the thyroid became normal within eight days, TSH after 3.8 days and serum thyroxine after three days. Serum triiodothyronine concentration remained elevated for several weeks, presumably as a result of the persisting iodine deficiency. The results indicate that a neonatal screening programme for hypothyroidism is as essential as adding iodine to table salt for avoiding neonatal and foetal maldevelopment.