Sitting to standing postural changes: Energy expenditure and a possible mechanism to alleviate sedentary behavior.

Background and aims Sedentary lifestyles have recently been identified as potential mechanism for obesity and associated metabolic diseases linked to ill health. The aim of this study was to investigate the effects of standing and sitting-standing positional changes on energy cost and consequently interrupting sedentary sitting time while working. Methods A total of 26 healthy male volunteers performed normal typing and editing work for 100 min under three conditions. The conditions included sustained sitting, sustained standing, and sitting-standing alternation every 20 min using a sit-stand desk. Respiratory parameters measured included minute ventilation (VE), oxygen consumption (VO2), and energy expenditure (EE). Measurements were recorded using a calibrated Cosmed K4b2 portable gas analysis system. Results The mean value for VE was the highest in the standing position (VE = 13.33 ± 0.71), followed by sitting-standing alternation (VE = 12.04 ± 0.62). Both were significantly different from sitting (VE = 10.59 ± 0.69). The maximum VE and EE for standing (VE = 14.81 ± 0.43 and EE = 1.84 ± 0.10) and sitting-standing alternation (VE = 14.80 ± 0.40 and EE = 1.93 ± 0.08) were significantly higher than that of sitting (VE = 12.15 ± 0.42 and EE = 1.67 ± 0.07). No significant differences were observed in the mean VO2 among the three conditions. However, the maximum VO2 for both standing (VO2 = 5.40 ± 0.20) and sitting-standing alternation (VO2 = 5.14 ± 0.17) had shown to be significantly higher than sitting (VO2 = 4.50 ± 0.18). There were no significant differences observed in the mean EE levels between sitting (EE = 1.43 ± 0.07) and sitting-standing alternation (EE = 1.55 ± 0.08). However, the mean EE while standing (EE = 1.62 ± 0.09) significantly increased compared to sitting. Conclusions The findings of this study indicate that sitting-standing alternations may be implemented as an effective intervention to interrupt prolonged sitting while working.

NSD1 duplication in Silver-Russell syndrome (SRS): molecular karyotyping in patients with SRS features.

Silver-Russell syndrome (SRS) is a growth retardation syndrome characterized by intrauterine and postnatal growth retardation, relative macrocephaly and protruding forehead, body asymmetry and feeding difficulties. Nearly 50% of cases show a hypomethylation in 11p15.5, in 10% maternal uniparental disomy of chromosome 7 is present. A significant number of patients with SRS features also exhibit chromosomal aberrations. We analyzed 43 individuals referred for SRS genetic testing by molecular karyotyping. Pathogenic variants could be detected in five of them, including a NSD1 duplication in 5q35 and a 14q32 microdeletion. NSD1 deletions are detectable in overgrowth disorders (Sotos syndrome and Beckwith-Wiedemann syndrome), whereas NSD1 duplications are associated with growth retardation. The 14q32 deletion is typically associated with Temple syndrome (TS14), but the identification of a patient in our cohort reflects the clinical overlap between TS14 and SRS. As determination of molecular subtypes is the basis for a directed counseling and therapy, the identification of pathogenic variants in >10% of the total cohort of patients referred for SRS testing and in >16% of characteristic individuals with the characteristic SRS phenotype confirms the need to apply molecular karyotyping in this cohort.

Dysfunction of SHANK2 and CHRNA7 in a patient with intellectual disability and language impairment supports genetic epistasis of the two loci.

Synaptopathies constitute a group of neurological diseases including autism spectrum disorders (ASD) and intellectual disability (ID). They have been associated with mutations in genes encoding proteins important for the formation and stabilization of synapses, such as SHANK1-3. Loss-of-function mutations in the SHANK genes have been identified in individuals with ASD and ID suggesting that other factors modify the neurological phenotype. We report a boy with severe ID, behavioral anomalies, and language impairment who carries a balanced de novo triple translocation 46,XY,t(11;17;19)(q13.3;q25.1;q13.42). The 11q13.3 breakpoint was found to disrupt the SHANK2 gene. The patient also carries copy number variations at 15q13.3 and 10q22.11 encompassing ARHGAP11B and two synaptic genes. The CHRNA7 gene encoding α7-nicotinic acetylcholine receptor subunit and the GPRIN2 gene encoding G-protein-regulated inducer of neurite growth 2 were duplicated. Co-occurrence of a de novo SHANK2 mutation and a CHRNA7 duplication in two reported patients with ASD and ID as well as in the patient with t(11;17;19), severe ID and behavior problems suggests convergence of these genes on a common synaptic pathway. Our results strengthen the oligogenic inheritance model and highlight the presence of a large effect mutation and modifier genes collectively determining phenotypic expression of the synaptopathy.

Y-chromosome markers in Turner syndrome: Screening of 130 patients.

BACKGROUND: The presence of Y-chromosome material in patients with Turner syndrome (TS) is a risk factor for the development of gonadoblastoma. Cytogenetic analysis detects Y-chromosome mosaicism in about 5% of Turner patients. However, if Y-chromosome sequences are present in only a few cells, they may be missed by routine analysis. The use of molecular techniques to detect the presence of Y-chromosome fragments in such patients is becoming increasingly important. AIM: The objective of our study was to analyze cryptic Y-chromosome derivatives in Hungarian TS patient population by real-time PCR (RT-PCR). SUBJECTS AND METHODS: Cytogenetic and RT-PCR methods were used to examine peripheral blood DNA of 130 Hungarian patients with TS for the presence of Y-chromosome. With RT-PCR, 4 regions throughout the Y-chromosome were analyzed. RESULTS: Initial cytogenetic karyotyping assessing 10-50 metaphases revealed 3 patients with Y-chromosome positivity. RT-PCR revealed further 6 patients with Y-chromosome, who were initially considered as Y-negatives by standard kayotyping. The consecutive cytogenetic analysis of a large number (about 100) of metaphases (in 5 patients) and/or FISH (in 6 patients) however, also confirmed the presence of the Y-chromosome in these patients. Prophylactic gonadectomy was carried out in all 9 patients and 1 of them was diagnosed as having bilateral gonadoblastoma without clinical symptoms. CONCLUSIONS: We recommend a routine molecular screening for hidden Y-chromosome sequences in Turner patients, who are negative for Y-chromosome by conventional cytogenetic analysis, in order to calculate the future risk of developing gonadoblastoma.

Superiority of tacrolimus 0.1% ointment compared with fluticasone 0.005% in adults with moderate to severe atopic dermatitis of the face: results from a randomized, double-blind trial.

BACKGROUND: No specific data are available on tacrolimus ointment as a second-line treatment in adults with facial eczema. OBJECTIVES: To compare tacrolimus 0.1% and fluticasone 0.005% ointments in adults with moderate to severe atopic dermatitis (AD) of the face in whom conventional treatment was ineffective or poorly tolerated. METHODS: Patients were randomized to double-blind treatment of facial AD with twice-daily tacrolimus ointment (n = 288) or fluticasone ointment (n = 280) for 3 weeks or until clearance. After day 21, patients could continue without the study treatment, apply the same ointment once daily, or switch to the other medication twice daily, depending on lesion clearance and patient/physician satisfaction. The primary endpoint was the day-21 response [> or = 60% reduction in the modified Local Eczema and Severity Index (mLEASI) score]. Secondary endpoints included facial erythema and pruritus, global clinical response, treatment switching at day 21 and safety. RESULTS Response with tacrolimus ointment (93%) was superior to that with fluticasone (88%; P = 0.026). Improvements in mLEASI components were also greater with tacrolimus ointment. Facial erythema and pruritus improved in both groups. Global clinical response was rated 'marked improvement' or better in 88% and 79% of patients in the tacrolimus ointment and fluticasone groups, respectively. At day 21, 9% of patients switched from fluticasone to tacrolimus ointment, while 4.5% switched from tacrolimus ointment to fluticasone. Adverse events were more frequent with tacrolimus ointment as a result of the higher incidence of application-site skin burning sensation. Safety of both drugs was in line with their respective summary of product characteristics. CONCLUSIONS: Tacrolimus 0.1% ointment has superior efficacy to fluticasone 0.005% ointment for twice-daily treatment of adults with moderate to severe facial AD in whom conventional therapy was inadequately effective or not tolerated. Tacrolimus 0.1% ointment is a safe and effective second-line treatment for the control of moderate to severe AD of the face.

Laterality disturbance and hypopituitarism. A case report of co-existing situs inversus totalis and combined pituitary hormone deficiency.

The authors present the case history of a 52-yr-old male patient with a unique association of combined pituitary hormone deficiency (CPHD) and situs inversus totalis. Except for signs and symptoms of pituitary hormone deficiency, the patient had no dysmorphic features, and hearing impairment, primary mental or neurological defects were also absent. Pituitary magnetic resonance imaging (MRI) scan showed hypoplasia of the anterior lobe of the pituitary gland and an ectopic posterior pituitary lobe. Despite the presence of situs inversus totalis, the patient was right-handed and functional MRI demonstrated left-hemisphere activation during language tests. Kartagener syndrome was considered, but immunofluorescence analysis showed normal localization of the outer dynein arm protein in respiratory epithelial cells obtained from the nasal mucosa. Direct DNA sequencing of all coding exons of the pituitary transcription factor 1 (PIT1) and prophet of PIT1 (PROP1) genes failed to detect disease-causing mutations, suggesting that these genes were not involved in the development of CPHD in our patient. More interestingly, the potential role of the paired like homeodomain transcription factor 2 (PITX2) gene, which has been implicated not only in CPHD, but also in left-right patterning in animal models, was also excluded, as sequencing showed the absence of mutations in coding exons of this gene. To our knowledge, PITX2 gene mutations have not been investigated in CPHD patients who had situs inversus totalis. We conclude that in contrast to animal models, the PITX2 gene is not involved in the development of situs inversus totalis, at least not in our CPHD patient.

Synergistic interaction of ABCB1 and ABCG2 polymorphisms predicts the prevalence of toxic encephalopathy during anticancer chemotherapy.

Polymorphisms of the ABCB1 (MDR1) and ABCG2 (BCRP) genes were reported to alter the expression and function of these drug transporters. Both proteins are present at the main pharmacokinetic barriers including the blood-brain barrier. Data from 291 children with acute lymphoblastic leukaemia were analysed in this retrospective study. ABCB1 3435T>C, 2677G>T/A, 1236C>T and ABCG2 421C>A, 34G>A genotypes were determined. Encephalopathy episodes were more frequent among those with ABCB1 3435TT genotype than in the 3435CC/CT group (odds ratio (OR) 3.5; P=0.03). Patients with the ABCG2 421A allele tended to have more complications than wild type homozygotes (OR=2.0; P=0.25). The rate of the adverse effect was similar in those harbouring no or only one of the predisposing genotypes, that is, either ABCB1 3435TT or ABCG2 421AA/AC. However, significantly more children suffered encephalopathy in the group with both predisposing genotypes (OR=12.3; P=0.005). In conclusion, these variations exert synergistic effect in predisposing patients to toxic neurological complications of chemotherapy.

National registry of patients with juvenile idiopathic inflammatory myopathies in Hungary--clinical characteristics and disease course of 44 patients with juvenile dermatomyositis.

Idiopathic inflammatory myopathies (IIMs) are systemic autoimmune diseases characterized by chronic muscle inflammation resulting in progressive weakness and frequent involvement of internal organs, mainly the pulmonary, gastrointestinal and cardiac systems which considerably contribute to the morbidity and mortality of the IIMs. Aim of this study was to present clinical characteristics, disease course, frequency of relapses and survival in patients with juvenile dermatomyositis (DM). A national registry of patients with juvenile IIMs was elaborated by the authors in Hungary. We have summarized data of the register according to signs and symptoms, disease course, frequency of relapses and survival of patients with juvenile IIM. Analysis was performed using data of 44 patients with juvenile DM diagnosed between 1976 and 2004 according to Bohan and Peter's criteria. Survival probability was calculated by Kaplan-Meier method. Data of patients with juvenile DM were compared with data of 66 patients with adult DM. The most frequent cutaneous features were facial erythema and heliotrope rash. Extramuscular and extraskeletal manifestations of the disease were more frequent in adult patients. The most common extramuscular feature was arthralgia in both groups of patients with juvenile or adult DM. Cardiac manifestation of the disease was not observed in juvenile patients. Respiratory muscle involvement and interstitial lung disease (ILD) were more frequent among adult DM patients than cardiac manifestation of the myositis. In view of the disease course, the authors found that frequency of polycyclic and monophasic subtypes of the disease were mainly similar. The hazard of relapse was found higher during the first year after the remission. None of the juvenile patients died. Among adult patients four disease-specific deaths occurred. There was no correlation between relapse free survival and initial therapeutic regimen. Many of our patients had polycyclic or chronic disease. As relapses can occur after a prolonged disease-free interval, patients should be followed up for at least 2 years. Although we found favourable survival probability, further investigations are needed to assess functional outcome.

Mutational spectrum of steroid 21-hydroxylase and the genotype-phenotype association in Middle European patients with congenital adrenal hyperplasia.

OBJECTIVE: To analyze the mutational spectrum of steroid 21-hydroxylase (CYP21) and the genotype- phenotype correlation in patients with congenital adrenal hyperplasia (CAH) registered in the Middle European Society for Pediatric Endocrinology CAH database, and to design a reliable and rational approach for CYP21 mutation detection in Middle European populations. DESIGN AND METHODS: Molecular analysis of the CYP21 gene was performed in 432 CAH patients and 298 family members. Low-resolution genotyping was performed to detect the eight most common point mutations. High-resolution genotyping, including Southern blotting and sequencing was performed to detect CYP21 gene deletions, conversions, point mutations or other sequence changes. RESULTS: CYP21 gene deletion and In2 and Ile172Asn mutation accounted for 72.7% of the affected alleles in the whole study group. A good genotype-phenotype correlation was observed, with the exception of Ile172Asn and Pro30Leu mutations. In 37% of patients low resolution genotyping could not identify the causative mutation or distinguish homozygosity from hemizygosity. Using high-resolution genotyping, the causative mutations could be identified in 341 out of 348 analyzed patients. A novel mutation Gln315Stop was found in one simple virilising CAH (SV-CAH) patient from Austria. In the remaining seven patients polymorphisms were identified as the leading sequence alteration. The presence of elevated basal and ACTH-stimulated 17-hydroxyprogesterone, premature pubarche, advanced bone age and clitoral hypertrophy directly implicated Asn493Ser polymorphism in the manifestation of nonclassical- (NC) and even SV-CAH. CONCLUSIONS: By genotyping for the most common point mutations, CYP21 gene deletion/conversion and the 8 bp deletion in exon 3, it should be possible to identify the mutation in 94-99% of the diseased alleles in any investigated Middle European population. In patients with a mild form of the disease and no detectable mutation CYP21 gene polymorphisms should be considered as a plausible disease-causing mutation.

Disease course, frequency of relapses and survival of 73 patients with juvenile or adult dermatomyositis.

OBJECTIVE: Our aim is to present the disease course, frequency of relapses and survival of juvenile and adult dermatomyositis (JDM/DM) patients. METHODS: Analysis was performed using data on 73 patients. The median follow-up for 38 JDM patients was 32 months and 78 months for 35 adult DM patients. RESULTS: 23/38 JDM patients (60%) had monophasic, 12/38 (31.6%) had polycyclic and 3/38 (7.9%) had chronic disease. Among children treated only with glucocorticoids, 12/20 (60%) had monophasic and 8/20 (40%) had polycyclic disease. 10/17 (58.8%) children, who required second-line immunosuppressive agents, had monophasic and 4/17 (23.5%) had polycyclic disease. 18/35 DM (51.4%) patients had monophasic, 13/35 (37.1%) had polycyclic, 1/35 (2.9%) had chronic disease and 3/35 (8.6%) had fulminant myositis. Among DM patients requiring only glucocorticoids, 12/20 (60%) were monophasic and 8/20 (40%) were polycyclic. In patients requiring second-line immunosuppressive agents, 6/15 patients (40%) had monophasic and 5/15 (33.3%) had polycyclic disease. Among patients with polycyclic disease, the risk of relapse was higher during first year than later in the disease course. None of the JDM patients have died, while 4 disease-specific deaths occurred in adult patients. There was no significant difference between the survival of JDM and DM patients. DISCUSSION: There was no correlation between relapse-free survival and the initial therapeutic regimen. Many of our patients had polycyclic or chronic disease. As relapses can occur after a prolonged disease-free interval, patients should be followed for at least 2 years. Although we found a favourable survival rate, further investigations are needed to assess functional outcome.

Limited value of serum steroid measurements in identification of mild form of 21-hydroxylase deficiency.

BACKGROUND: ACTH stimulation test is widely used as a basic diagnostic method for non-classical congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency (21-OHD). However, the interpretation of this test has not been definitely established. To determine the cut-off values of basal and post-ACTH serum 17-OHP concentrations, data of patients with suspected 21-OHD has been analysed. PATIENTS AND METHODS: Two hundred and eighty-seven patients with postnatal/peripubertal virilization were investigated. Serum steroid concentrations were measured by RIA, urinary steroid profile was determined by capillary gas chromatography and mutation analysis of CYP21 gene was performed by allele specific PCR. 21-OHD was diagnosed by elevated serum 17-OHP concentrations, high level of the urinary 17-OHP metabolites and/or homozygosity for CYP21 mutations. RESULTS: Twenty-one patients of the total of 287 subjects (7.3 %) were identified as having 21-OHD. The numbers of 21-OHD patients compared to total numbers of patients with different ranges of serum 17-OHP were as follows: basal values below 3.5 ng/ml (mean + 1 SD) 0/225; between 3.5 - 6.6 ng/ml 3/41; above 6.6 ng/ml (mean + 2 SD) 18/21. Post-ACTH values below 6.4 ng/ml (mean + 1 SD) 0/226, between 6.4 - 10.3 ng/ml 0/35, above 10.3 ng/ml (mean + 2 SD) 21/26. CONCLUSION: There are patients with inappropriate peripubertal virilization who have slightly elevated 17-OHP concentrations. In this subgroup of patients more sensitive and specific methods are needed to establish the diagnosis of 21-OHD. Therefore we suggest performing an ACTH stimulation test in patients with a morning 17-OHP level above 3.5 ng/ml. Furthermore, urinary steroid profile and/or CYP21 gene analysis are needed in patients with a stimulated 17-OHP value between 10 and 30 ng/ml. These tests will distinguish between patients with non-classical 21-OHD and patients with other disorders.

Terbinafine (Lamisil) treatment of toenail onychomycosis in patients with insulin-dependent and non-insulin-dependent diabetes mellitus: a multicentre trial.

BACKGROUND: Diabetes mellitus (DM) affects an estimated 175 million people world-wide. Approximately one-third of patients with DM have toenail onychomycosis. OBJECTIVES: To determine the efficacy and safety of terbinafine treatment of toenail onychomycosis in patients with DM receiving insulin and/or oral antidiabetic agents. Special interest was focused on potential drug interactions with oral hypoglycaemic substances. METHODS: In a multicentre trial, patients suffering from insulin-dependent DM (IDDM) or non- insulin-dependent DM (NIDDM) with toenail onychomycosis were treated for 12 weeks with oral terbinafine 250 mg daily and followed up to 48 weeks. In addition to clinical, mycological and laboratory investigations, blood glucose levels were monitored. RESULTS: At the end of the trial (week 48), a mycological cure rate of 73% was achieved. The rates of clinical cure and complete cure (mycological cure plus clinical cure) were 57% and 48%, respectively. There was no statistically significant difference between the NIDDM and IDDM groups with respect to the cure rates (P > 0.05). No hypoglycaemic episode was reported and none of the patients had hypoglycaemia during the treatment phase. CONCLUSIONS: With excellent cure rates and a good tolerability profile, terbinafine should continue to be a drug of choice for the treatment of toenail onychomycosis in the rising number of NIDDM patients receiving multiple medication.

Differences by sex in cardiovascular disease in Williams syndrome.

OBJECTIVE: To analyze the incidence and severity of cardiovascular disease in patients with Williams syndrome (WS) and to identify factors contributing to its variable expression. METHODS: Clinical data on patients with WS were collected from several WS centers. Elastin gene deletions were confirmed in all patients. Age at diagnosis, growth data, and cardiovascular diagnoses were recorded retrospectively. Cardiac diagnoses were made on the basis of echocardiographic data. The severity of supravalvular aortic stenosis was recorded by using a 4-step scale (none, mild, moderate, severe). RESULTS: Statistical analysis of the data revealed that the severity of both supravalvular aortic stenosis and total cardiovascular disease was significantly greater in male patients than female patients (P <.002 and P <.002, respectively; Kruskal-Wallis rank-sum test). This difference was not accounted for by differences in height, weight, body mass index, or head circumference. The clinical diagnosis of WS was made at a significantly younger age in male patients (P <.01, Student t test). Earlier diagnosis was partly because of increased incidence and severity of cardiovascular disease. Another determinant of early diagnosis was low body mass index. CONCLUSION: Penetrance and severity of the elastin arteriopathy in patients with WS is affected by sex. We hypothesize that differences by sex in arterial stenoses may be related to prenatal hormonal effects. Future epidemiologic and in vitro studies may provide additional insight into the pathogenetic mechanisms of these observed differences.

[Androgen insensitivity syndrome. Clinical features and molecular genetics]. / Androgen insensitivitas syndroma. Klinikai és molekuláris genetikai spektrum.

Androgen insensitivity syndrome (AIS) is an X-linked hereditary disorder caused by the mutation of the androgen receptor gene leading to variable phenotypes according to the depth of the hormonal resistance. There is a lack of knowledge regarding the criteria used to decide the management of infants with partial AIS, particularly with respect to sex of rearing. Therefore a national survey of patients with AIS in Hungary has been decided to compose a database for analyzing current practice. Preliminary results of the analysis for the mutations in the androgen receptor gene of Hungarian patients with AIS has been presented. The authors suggest that guidelines for clinicians on appropriate diagnostic and management strategies for AIS patients, particularly in the case of suspected partial AIS, would be helpful.

Prenatal diagnosis of steroid 21-hydroxylase deficiency by allele-specific amplification.

OBJECTIVE: Congenital adrenal hyperplasia due to steroid 21-hydroxylase deficiency (21-OHD) is the most common cause of ambiguous genitalia in females at birth. Here, we report the first prenatal diagnosis of 21-OHD by DNA analysis in Hungary. METHODS: Allele-specific amplification (ASA) of the DNA obtained by chorionic villus sampling was performed. RESULTS: The fetus had a homozygous nonsense mutation (Gln318Stop), suggesting a salt-wasting phenotype. Dexamethasone treatment of the mother was started on the 8th gestational week and, as the fetus was an affected female, it was continued until term. The newborn had normal external genitalia at birth, and severe salt-wasting crisis and postnatal virilization was prevented by mineralo- and glucocorticoid replacement therapy. CONCLUSION: 21-OHD was genotyped by ASA, and virilization of the fetus was prevented by antenatal dexamethasone therapy.

[Life expectancy in Down syndrome infants and children with congenital heart defects, 1974-1997]. / A Down-szindrómás szívbeteg csecsemók és gyermekek életkilátása 1974-1997 között.

Authors analysed 359 cases with Down's syndrome and congenital heart defects registered between 1974-1997 in Hungary. The total death rate was 19.9% (70 cases). Mortality in the operated group (85 cases) was 10.5% (9 patients), in the non-operated group (274 cases) 22.2% (61 patients). The death rate was lower in the group with early primary reconstruction (2.3%) than in the group with palliation + reconstruction (15.3%), or in the group with only palliative procedure (20%). These results indicate that the life expectancy of infants and children with Down's syndrome and congenital heart disease after early primary reconstructive procedure is the same as in Down syndrome patients without cardiac defects. The prognosis depends on the patient's social circumstances. The results after correct surgical procedure in patients with the same cardiac defect are similar to that of the patients with or without Down's syndrome.

[Aberrations of chromosome 18 and their significance in genetic counseling]. / A 18-as kromoszóma rendellenességeinek eredete és jelentósége a genetikai tanácsadásban.

In order to get information on the origin of chromosome 18 aberrations trisomy 18 cases were analysed as well as different chromosome 18 rearrangements. In total, their study population consisted of 100 trisomy 18 patients and their parents, 67 out of which have already been published. Additionally, seven families were analysed with structural aberrations of chromosome 18 including four patients with tetrasomy 18p. Determination of parent and cell stage of origin was performed by short tandem repeat typing (STR, microsatellites). These investigations revealed that the additional chromosomal material in the majority of the chromosomal 18 aberrations was maternal in origin (97/107). In most of the cases the nondisjunction occurred during maternal meiosis II. This was in agreement with findings of other groups. Thus, independently from the type of aberration, there was a predisposition of chromosome 18 for nondisjunction in maternal meiosis II. In this respect, chromosome 18 seemed to be unique among human autosomes. Furthermore, these results showed that molecular genetic analyses of chromosomal aberrations and their formation mechanisms were meaningful tools in genetic counselling situations: in 5 cases where cytogenetic investigations could not performed, the clinical diagnosis of Edwards syndrome could be confirmed by molecular findings. Thus, in these cases other genetic diseases with differing types of inheritance could be excluded from being the cause of the observed malformations. In a further structural rearrangement of chromosome 18, the origin could be determined as being mitotic, therefore a recurrence risk could be excluded for this couple.

Screening for mutations of 21-hydroxylase gene in Hungarian patients with congenital adrenal hyperplasia.

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive disorders, causing impaired secretion of cortisol and aldosterone from the adrenal cortex, with subsequent overproduction of adrenal androgens. The most common enzyme defect causing CAH is steroid 21-hydroxylase deficiency. To determine the mutational spectrum in the Hungarian CAH population, the CYP21 active gene was analyzed using PCR. A total of 297 Hungarian patients with 21-hydroxylase deficiency are registered in the 2nd Department of Pediatrics, Budapest, Hungary, and their clinical status was evaluated. Blood samples for CYP21 genotype determination could be obtained from 167 patients (representing 306 unrelated chromosomes and 56.2% of the total group of patients). Eight of the most common mutations were screened [In2 (intron 2 splice mutation), I172N, Del (Del: apparents large gene conversion), Q318X, R356W, 1761Tins, ClusterE6, V281L] using allele-specific amplification. The most frequent mutation in the Hungarian CAH population was found to be In2. Our results have shown a good genotype/phenotype correlation in case of most mutations; the In2 mutation is associated mostly with the severe form of the disease, whereas I172N was expressed in a wide spectrum of phenotypes. 1999)

Screening of patients with Turner syndrome for "hidden" Y-mosaicism.

The presence of Y-chromosomal sequences in the cells of patients with Turner-Syndrome (TS) is a risk factor for the development of gonadal tumors. Therefore and since demonstration of Y-material usually results in prophylactic gonadectomy optimal sensitivity and specificity of the diagnosis have to be attempted. We wanted to evaluate the diagnostic potential of cytogenetic investigations as routinely employed in TS. In the most comprehensive study published so far we screened 208 TS patients for the presence of Y-chromosomal sequences by polymerase chain reaction (PCR) specific for eight different loci along the Y-chromosome. Six patients (3%) without cytogenetic evidence of Y-chromosome were found to be Y-positive. Among 12 cases with marker chromosomes two more Y-chromosomal fragments were identified. Thus, PCR-screening for Y-specific sequences was shown to be a valuable tool in the clinical management of Turner patients.