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PubMed2006

Public attitudes toward genetic testing: perceived benefits and objections.

The aim of this study was to assess public attitudes toward the availability and use of genetic tests to explore support for genomics developments and to help improve public discussion. Questionnaires to assess the assumed advantages and disadvantages of genetic testing were sent to a representative sample of the Dutch population (n = 1,308; age > or =25 years). The response was 63% (817/1,308). Two groups with extreme scores on a four-item scale were distinguished, representing opponents (n = 248) and supporters (n = 264) of the availability and use of genetic tests. Multiple logistic regression analyses showed that those who were familiar with a genetic disease (odds ratio [OR] 0.54; 95% confidence interval [CI] 0.32-0.89; p = 0.015), those who scored higher on a four-item scale on belief in personal benefits of testing (OR 0.29; 95% CI 0.21-0.40; p < 0.0001), and those who believe that knowledge of the genetic background of disease will help people to live more healthy lives (OR 0.48; 95% CI 0.37-0.62; p < 0.0001), were less likely to be opponents. Those who agreed that genetic testing is tampering with nature (OR 1.63; 95% CI 1.32-2.00; p < 0.0001) were more likely to be opponents. Other variables such as belief in genetic determinism, genetic knowledge, level of education, age, and gender were not significantly associated. These results suggest that in addition to moral acceptability, perceived usefulness is a precondition for supporting genetic testing. It is not expected that more information will necessarily result in more positive attitudes.

Adult↗

PubMed2004

Validity of a 5-meter multiple shuttle run test for assessing fitness of women field hockey players.

The aim of this study was to establish validity of a 5-m multiple shuttle test (5-m MST) using indirect (criterion and construct) and direct measures of performance. For criterion validity, comparisons were made between data from established fitness tests and a 5-m MST. Construct validity was determined by comparing results from a 5-m MST with subjects of different playing abilities. Direct validity was determined by comparing values attained from a 5-m MST with data from a time-motion study of field hockey. For criterion validity, the strongest relationship existed between the 20-m MST (42.7 +/- 7.1 ml.kg(-1).min(-1)) and total distance from the 5-m MST (650.9 +/- 59.2 m; r = 0.92). For construct validity, regional representative players covered more distance than club-level players (689.9 +/- 46.6 m vs. 661.1 +/- 31.0 m; p < 0.01). For direct validity, the highest correlation was found between total distance from the 5-m MST (706.0 +/- 37.5 m) and mean displacement during matches (61.0 +/- 6.0 m; r = 0.74). It was concluded that the 5-m MST had both indirect and direct validity for the fitness assessment of field hockey players. The data obtained from the 5-m MST directly relates to the physical fitness of the players during competition.

Adult↗

PubMed2006

Weak independent association signals between IDE polymorphisms, Alzheimer's disease and cognitive measures.

Functional and genetic studies suggest that insulin-degrading enzyme (IDE) may be a strong functional and positional candidate. As there is a lack of consensus in regards to the level and location of IDE association signals we aimed to clarify these discrepancies through genotyping 28 SNPs in a large case-control collective together with quantitative measures of cognitive ability (MMSE). Four SNPs (rs11187007, rs2149632_ide12, rs11187033, rs11187040) were found to be associated with AD (nominal p<0.01). Tests with MMSE scores adjusted for disease duration identified associations, with the most significant result for rs1999763 (nominal p=0.008). Similarly, different reconstructed IDE haplotypes were associated with AD and higher MMSE scores. The association signals are only borderline significant after adjustment for multiple testing, but add further evidence to previous published results on the association between IDE and AD or MMSE. A subgroup analysis indicated more prominent associations with AD in younger, and with MMSE in older patients. There may be two independent effects mediated by IDE variants, risk for AD and modification of disease progression.

Aged↗

PubMed2002

Measurement of ultraviolet radiation-induced suppression of recall contact and delayed-type hypersensitivity in humans.

This article describes methodology used for assessment of ultraviolet radiation-induced suppression of recall responses in humans. Nickel allergy is common in the general population and patch testing of nickel-allergic volunteers provides a convenient model of contact hypersensitivity. Similarly, Mantoux-positive volunteers, recruited from within hospital staff, are used as a model for delayed-type hypersensitivity. Use of secondary rather than primary immune responses allows placement of multiple test sites on each volunteer. Further, each volunteer acts as his or her own unirradiated control. This enables UV immunosuppression to be studied with relatively few human volunteers, and makes determination of UV immunosuppression dose responses feasible in human subjects. The method can also be used for assessment of the level of immune protection afforded by agents such as sunscreens or biologically active substances.

Dermatitis, Contact↗

PubMed2004

Physiologic profile of recreational male and female novice and experienced Tae Kwon Do practitioners.

AIM: Subjects, 28 recreational male and female novice and experienced Tae Kwon Do practitioners (age 19-42 years), were examined on 6 physiological parameters: body composition (BF%, skinfold measures), flexibility (sit-and-reach and leg-splits tests), lower and upper-body dynamic muscular strength (leg press and bench press), abdominal strength and endurance (1-minute timed, bent-knee sit-ups test), lower extremity explosive power (vertical jump-and-reach test), and cardiovascular endurance (graded exercise treadmill test). METHODS: Subjects were assigned to 1 of the 4 following groups: Tae Kwon Do experienced and trained men (MT), Tae Kwon Do experienced and trained women (FT), novice Tae Kwon Do men (MN), and novice Tae Kwon Do women (FN). RESULTS: Results of multiple testing procedures and comparison across groups indicated that Tae Kwon Do black belts were more athletically fit as compared with that of novice Tae Kwon Do practitioners of the same sex in spite of the fact that male and female black belts were older than their novice counterparts. Experienced Tae Kwon Do subjects were stronger as measured by lower body strength and showed better aerobic performance capacity as well as lower percent body fat. Additionally, MT subjects demonstrated higher flexibility. CONCLUSION: The highly diverse training, repeated and continuous use of the legs and arms alone or combined with maximal stretching, and high intensity exercise may account for observed differences among groups.

Adaptation, Physiological↗

PubMed2004

Identifying space-time disease clusters.

A cluster of cases of disease that are close both in space and in time is suggestive of an infectious aetiology. We present statistical tests for space-time clusters of disease for the two situations where the population at risk is either known or unknown as a function of space and time. The tests are derived using standard statistical methodology from a simple mathematical model of disease spread, i.e. they are derived as score tests from a likelihood function in which the infection process is modelled as a point process whose intensity becomes greater near an infector. A problem for such tests is that, when investigating whether or not a disease may be of infectious origin, the space and time distances characterising closeness to an infection are very likely to be unknown. The proposed methodology copes with this difficulty in a statistically acceptable way, without requiring multiple tests whose interpretation would be doubtful. When the underlying population size is unknown, the test reduces to a modification of the Knox test. An example of its use is given as epidemiology, risk, space-time cluster, likelihood and Knox test.

Animals↗

PubMed2004

Two variants in the resistin gene and the response to long-term overfeeding.

OBJECTIVE AND SUBJECTS: To investigate the role of resistin gene variants on the adiposity and metabolic changes observed in response to a 100-day overfeeding protocol conducted with 12 pairs of monozygotic twins. MEASUREMENTS: Body-fat measurements included hydrodensitometry and abdominal fat from computed tomography. Plasma glucose and insulin during fasting and in response to an oral glucose tolerance test (OGTT) were assayed. A 4.2 MJ test meal was consumed, after which calorimetric measurements were performed for 240 min. RESULTS: Respiratory quotient (RQ) decreased (P=0.001) more in AA/AG than in GG subjects of the IVS2+181G>A polymorphism after the caloric surplus and the significance persisted when correction for multiple testing was performed. Total abdominal (P=0.027) and visceral (P=0.004) fat increased more in TC than in TT subjects of the IVS2+39C>T polymorphism. In response to overfeeding, glucose area under the curve during the OGTT showed a slight decrease (P=0.031) in the TC while it increased in TT subjects. OGTT insulin area tended to increase less (P=0.055) in TC than in TT subjects. After overfeeding, fasting insulin was lower in TC than in TT subjects (P=0.010). In addition, TC subjects experienced more decrease in RQ than TT subjects (P=0.034). CONCLUSION: The IVS2+181G>A variant was associated with the changes in RQ in response to overfeeding. The IVS2+39C>T polymorphism was associated with overfeeding-induced changes in abdominal visceral fat, OGTT glucose area and RQ. The results suggest that sequence variation in the resistin gene is involved in the adaptation to chronic positive energy balance.

Adipose Tissue↗

PubMed2005

Cognitive performance of patients with mesial temporal lobe epilepsy and incidental calcified neurocysticercosis.

OBJECTIVES: Although chronic calcified neurocysticercosis (NCC) has been considered a major cause of symptomatic epilepsy in developing countries, it can also be an incidental pathological finding in epileptic patients from endemic regions. The mechanisms of brain plasticity occurring in patients with NCC during and after the inflammatory process related to the parasite infection, death, degeneration, and calcification within the host brain might be an independent factor for cognitive impairment in patients with NCC and epilepsy. In order to assess this possibility cognitive performance of patients with mesial temporal lobe epilepsy related to hippocampal sclerosis (MTLE-HS) with and without NCC was investigated through structured neuropsychological testing. METHODS: Cognitive performance of long term MTLE-HS patients with (HS-NCC group, n = 32) and without NCC (HS only, n = 48) was compared. Imbalances between the two groups with respect to clinical, demographic, neuroimaging, and electrophysiological variables were adjusted by linear multiple regression analysis and Bonferroni correction for multiple tests. RESULTS AND CONCLUSIONS: There were no cognitive performance differences between HS-NCC and HS only patients, leading to the conclusion that chronic calcified NCC per se does not aggravate the cognitive performance of patients with long term MTLE-HS.

Brain Diseases↗

PubMed2005

Mitochondrial genetic effects on latent class variables associated with susceptibility to alcoholism.

We report the results of statistical genetic analyses of data from the Collaborative Study on the Genetics of Alcoholism prepared for the Genetic Analysis Workshop 14 to detect and characterize maternally inherited mitochondrial genetic effects on variation in latent class psychiatric/behavioral variables employed in the diagnosis of alcoholism. Using published extensions to variance decomposition methods for statistical genetic analysis of continuous and discrete traits we: 1) estimated the proportion of the variance in each trait due to the effects of mitochondrial DNA (mtDNA), 2) tested for pleiotropy, both mitochondrial genetic and residual additive genetic, between trait pairs, and 3) evaluated whether the simultaneous estimation of mitochondrial genetic effects on these traits improves our ability to detect and localize quantitative trait loci (QTL) in the nuclear genome. After correction for multiple testing, we find significant (p < 0.009) mitochondrial genetic contributions to the variance for two latent class variables. Although we do detect significant residual additive genetic correlations between the two traits, there is no evidence of a residual mitochondrial genetic correlation between them. Evidence for autosomal QTL for these traits is improved when linkage screens are conditioned on significant mitochondrial genetic effects. We conclude that mitochondrial genes may contribute to variation in some latent class psychiatric/behavioral variables associated with alcoholism.

Alcoholism↗

PubMed2004

Power estimation of multiple SNP association test of case-control study and application.

At the current stage, a large number of single nucleotide polymorphisms (SNPs) have been deployed in searching for genes underlying complex diseases. A powerful method is desirable for efficient analysis of SNP data. Recently, a novel method for multiple SNP association test using a combination of allelic association (AA) and Hardy-Weinberg disequilibrium (HWD) has been proposed. However, the power of this test has not been systematically examined. In this study, we conducted a simulation study to further evaluate the statistical power of the new procedure, as well as of the influence of the HWD on its performance. The simulation examined the scenarios of multiple disease SNPs among a candidate pool, assuming different parameters including allele frequencies and risk ratios, dominant, additive, and recessive genetic models, and the existence of gene-gene interactions and linkage disequilibrium (LD). We also evaluated the performance of this test in capturing real disease associated SNPs, when a significant global P value is detected. Our results suggest that this new procedure is more powerful than conventional single-point analyses with correction of multiple testing. However, inclusion of HWD reduces the power under most circumstances. We applied the novel association test procedure to a case-control study of preterm delivery (PTD), examining the effects of 96 candidate gene SNPs concurrently, and detected a global P value of 0.0250 by using Cochran-Armitage chi(2)s as "starting" statistics in the procedure. In the following single point analysis, SNPs on IL1RN, IL1R2, ESR1, Factor 5, and OPRM1 genes were identified as possible risk factors in PTD.

Algorithms↗

PubMed2002

Gender differences in narcotic-induced emesis in the ED.

Narcotic analgesia is commonly given in the emergency department. Narcotic-induced nausea and vomiting is thought to be a common occurrence, but the gender incidence and associations are not well defined. The aim of this study was to document the sex-related complication of nausea and vomiting after opiate administration for pain relief in the ED. The study hypothesis was that men and women have the same rate of narcotic-induced emesis in the ED. A prospective, convenience study of the use of narcotic analgesic on patients in an innercity Level I Trauma Center was undertaken. Information concerning the reason for narcotics, complications, number of doses, and route of administration were studied. The emergency physicians were allowed clinical judgment to treat the patients with any narcotic agent in any dose increment. The data were entered into an SPSS program (Chicago, IL). Analysis between groups (men v women) was then conducted by an independent t test. We compared the 2 groups across 6 categories: cause of injury, presenting pain scale, first drug given, first dose given, first route of drug, and requires an anti-emetic. A Bonferroni procedure was used to correct for the higher probability of significant findings when multiple tests were performed. All findings that are significant are after Bonferroni. The study was Institutional Review Board (IRB) approved. A total of 325 consenting patients were studied from October 1996 to April 1998. The patients consisted of 174 men and 151 women, with an average of 35.8 years of age. The race of the patients was 70% African American and 20% Hispanic. Of the total of 325 patients, 20.3% (74) required an anti-emetic because of nausea and/or vomiting. A significant difference occurred in causes of pain for women (t = 2.79, P <.007). The causes of pain for women were general pain, fracture, abdominal, back pain, and other as compared with men with gun shot wounds, general, fracture, low back, and flank. Women showed no significant difference with regard to presenting pain scale (t =.122, P <.903), first drug given (t = 1.643, P <.101), and first dose given (t =.708, P <.408). The majority of patients received morphine (55.4%), followed by meperidine (24.3%), and hydrocodone (13.5%). The most frequent route of administration was intravenous (IV, 45.2%), intramuscular (IM, 35.7%), with oral being the least frequent route (19.1%). There was a difference for women with first route given (t = 2.543, P <.01) and requires anti-emetic (t = 3.06, P <.002). The majority of women received IM (58.6%) versus IV (37.7%), whereas the majority of men (62.3%) received IV versus IM (41.4%). A significant number of patients became nauseated and/or vomited from Emergency Department-administered narcotics. The nausea and vomiting was associated with female sex and the cause of pain. A comparative study of other pain medications versus narcotics for incidence of induced nausea and emesis would be useful.

Adolescent↗

PubMed2005

A novel framework for sib pair linkage analysis.

Sib pair linkage analysis of a dichotomous trait is a popular method for narrowing the search for genes that influence complex diseases. Although the pedigree structures are uncomplicated and the underlying genetic principles straightforward, a surprising degree of complexity is involved in implementing a sib pair study and interpreting the results. Ascertainment may be based on affected, discordant, or unaffected sib pairs, as well as on pairs defined by threshold values for quantitative traits, such as extreme discordant sib pairs. To optimize power, various domain restrictions and null hypotheses have been proposed for each of these designs, yielding a wide array of choices for the analyst. To begin, we systematically classify the major sources of discretion in sib pair linkage analysis. Then, we extend the work of Kruglyak and Lander (1995), to bring the various forms into a unified framework and to facilitate a more general approach to the analysis. Finally, we describe a new, freely available computer program, Splat (Sib Pair Linkage Analysis Testing), that can perform any sib pair statistical test currently in use, as well as any user-defined test yet to be proposed. Splat uses the expectation maximization algorithm to calculate maximum-likelihood estimates of sharing (subject to user-specified conditions) and then plots LOD scores versus chromosomal position. It includes a novel grid-scanning capability that enables simultaneous visualization of multiple test statistics. This can lead to further insight into the genetic basis of the disease process under consideration. In addition, phenotype definitions can be modified without the recalculation of inheritance vectors, thereby providing considerable flexibility for exploratory analysis. The application of Splat will be illustrated with data from studies on the genetics of diabetic nephropathy.

Algorithms↗

PubMed2001

Comparison of antimicrobial in vitro activities against Streptococcus pneumoniae independent of MIC susceptibility breakpoints using MIC frequency distribution curves, scattergrams and linear regression analyses.

Comparing in vitro activities of antimicrobial agents against Streptococcus pneumoniae using per cent susceptible to recommended MIC breakpoints is not optimal. In this study, MICs of penicillin G, ampicillin/sulbactam, ceftriaxone, cefuroxime, erythromycin, tetracycline, trimethoprim/sulfamethoxazole, ciprofloxacin, levofloxacin, trovafloxacin and moxifloxacin were determined for 646 strains. Drug activities were compared using MIC frequency distribution curves, scattergrams and linear regression analyses of MICs (log2). MIC frequency distributions did not always correspond to recommended breakpoints for distinguishing susceptible, intermediate and resistant strains. Penicillin G, ampicillin/sulbactam and ceftriaxone had similar activities and were each c. 1-1.5 dilution steps more active than cefuroxime. For all beta-lactam drug pairs, there was a high correlation of MICs with regression line slopes (a approximately equal to 1) and coefficients of determination (R(2) = 0.90-0.97). Although beta-lactam-resistant strains were more likely to be resistant to erythromycin, tetracycline and/or trimethoprim/sulfamethoxazole than were beta-lactam-susceptible strains, MIC correlations were relatively poor (R(2) = 0.14-0.46), as they were when the non-beta-lactam drugs were compared with each other (R(2) = 0.10-0.25). Trovafloxacin and moxifloxacin were each c. 2.5 dilution steps more active than ciprofloxacin and levofloxacin. There was no correlation of quinolone MICs with MICs of any other drug class (R(2) 0.02). Among the quinolones, however, there was a high correlation of MICs with a approximately equal to 1 and R(2) = 0.81-0.92. With the quinolone drug pairs, lines of best fit were second-order polynomial equations, consistent with a dissociation of low level resistance mechanisms. In summary, beta-lactam and quinolone MICs were predictable within drug classes and testing multiple derivatives within each class is probably not necessary. Although there was some relationship between beta-lactam, erythromycin, tetracycline and trimethoprim/sulfamethoxazole MICs, predictability of MICs between drug classes was poor. There was no relationship between quinolone MICs and MICs of any of the other drugs tested.

4-Quinolones↗

PubMed2005

Evidence for susceptibility determinant(s) to psoriasis vulgaris in or near PTPN22 in German patients.

INTRODUCTION: Variant R620W of protein tyrosine phosphatase non-receptor type 22 (PTPN22) has consistently been reported as a susceptibility factor for several autoimmune diseases. We investigated its role in susceptibility to psoriasis, the relevance of possibly other disease-causing variants, and interdependency of the major risk factor for psoriasis at PSORS1. METHODS: R620W was tested in a case-control study initially with 375 German patients and then with an enlarged sample of an additional 418 patients. Analyses were extended to linkage disequilibrium (LD) based haplotypes. Potential interaction between risk haplotypes of PTPN22 and the PSORS1 associated risk allele was tested by regression analysis. PTPN22 coding sequence was determined in 20 patients carrying the risk haplotype. Association and regression analysis were also performed in the extended case-control study. RESULTS: R620W was not associated in either case-control study, while significant association (corrected for multiple testing) with one haplotype (C-4) of the LD block encompassing PTPN22 as well with another haplotype (B-3) within an adjacent telomeric LD block was detected. No evidence for interaction between risk haplotype C-4 and the PSORS1 associated risk allele was found. Sequencing excluded other coding variants within PTPN22 as a basis for association findings. Analysis of the extended study group confirmed association for haplotypes B-3 and C-4 and independence of risk haplotypes C-4 and PSORS1. DISCUSSION: We exclude a major role of *620W in German psoriasis patients but suggest that other susceptibility determinant(s) within non-coding regions of PTPN22 or its proximity might exist acting independently of the major PSORS1 risk factor.

Alleles↗

PubMed1977

The correlation of cold agglutinin titrations in saline and albumin with haemolytic anaemia.

Cold agglutinin syndrome (CAS) is usually associated with IgM cold agglutinins with titres exceeding 1000 at 4 degrees C and a thermal amplitude of 30-32 degrees C. Occasionally patients are encountered who although having clinical and laboratory findings compatible with CAS do not have the characteristic serological findings. Thirty-two patients with a positive direct antiglobulin test due to complement sensitization were studied. Thirty-one of these patients had cold agglutinin titres greater than 64. Twenty-eight had haemolytic anaemia, including one patient with a cold agglutinin titre of only 8 against saline-suspended red cells. 53.6% of sera from patients with haemolytic anaemia reacted at 30 degrees C and 7.1% at 37 degrees C when albumin was not present, whereas in the presence of albumin all of the sera reacted at 30 degrees C and 67.9% reacted at 37 degrees C. None of the four patients without haemolytic anaemia reacted at 30 degrees C or 37 degrees C in the presence of albumin, even though one serum reacted to a titre of 1280 at 4 degrees C. Cold agglutinin titres and thermal amplitudes in the presence of bovine albumin were found to correlate better with haemolytic anaemia than reactions without albumin. If bovine albumin is utilized in compatibility testing, multiple cold autoabsorptions may be necessary before alloantibody activity at 37 degrees C can be excluded.

Agglutinins↗

PubMed1997

Second-trimester maternal serum CA-125 versus estriol in the multiple-marker screening test for Down syndrome.

OBJECTIVE: To determine the ability of second-trimester maternal serum CA-125 levels to detect fetal Down syndrome. METHODS: From stored, second-trimester maternal serum analyzed previously with the multiple-marker screening test for fetal Down syndrome, we selected 306 samples from euploid pregnancies and 22 samples from Down syndrome pregnancies at 14-20 weeks' gestation. CA-125 levels were measured by enzyme-linked immunosorbent assay and converted to gestational week-specific multiples of the median (MoM). RESULTS: The mean maternal age (+/- standard deviation) of the study population was 35.5 +/- 5.3 years. The Down syndrome group CA-125 mean MoM was significantly higher than the euploid group mean MoM (1.47 +/- 0.51 MoM versus 1.05 +/- 0.44 MoM; P < .001). CA-125 at or above 1.5 MoM identified 10 of 22 (45%) Down syndrome cases. Substituting CA-125 for estriol (E3) in the multiple-marker screening test resulted in a lower screen-positive rate (67 of 328, 20% [95% confidence interval {CI} 16, 25] versus 91 of 328, 28% [95% CI 23, 33]) with a similar Down syndrome detection rate (18 of 22, 82%). Alternatively, when the screen-positive rate was held constant, the Down syndrome detection rate improved (20 of 22, 91% [95% CI 71, 99] versus 18 of 22, 82% [95% CI 60, 95]). CONCLUSIONS: Down syndrome pregnancies have higher second-trimester maternal serum CA-125 levels than euploid pregnancies. CA-125 may be superior to E3 in the multiple-marker screening test for fetal Down syndrome.

Adult↗

PubMed1989

Patterns of occult bleeding in asymptomatic colorectal cancer.

The assumption that asymptomatic colorectal cancers bleed provides the rationale for widespread stool screening. The authors studied 12 patients with unoperated colorectal cancer but without colorectal symptoms and six healthy volunteers as laboratory controls. All stools were collected for 2 weeks and analyzed by the HemoQuant and Hemoccult tests. In controls, the mean HemoQuant value was 0.7 mg hemoglobin (Hb)/g stool (range, 0.1-1.8) and all stools were Hemoccult-negative. In cancer patients, the mean HemoQuant was 3.3 mg Hb/g (range, 0.3-13.2); stools were within the normal HemoQuant range (less than 2 mg Hb/g) in 38% and negative by Hemoccult in 70%. The mean cancer detection rate testing a single stool per patient was 57% for HemoQuant and 25% for Hemoccult (P less than 0.001). The detection rate rose testing multiple stools and was maximal with five stools at 83% for HemoQuant compared to 31% for Hemoccult (P less than 0.001). The authors conclude that fecal blood levels are commonly normal with asymptomatic colorectal cancer. Although higher with HemoQuant than Hemoccult, cancer detection rates by fecal blood testing appear to be lower than previously reported.

Adenocarcinoma↗

PubMed1998

Transmission disequilibrium analysis of a triplet repeat within the hKCa3 gene using family trios with schizophrenia.

hKCa3 is a neuronal small conductance calcium-activated potassium channel which contains a polyglutamine tract, encoded by a polymorphic CAG repeat in the gene. Since an association between longer alleles of the CAG repeat and schizophrenia has been reported, we performed haplotype-based haplotype relative risk (HHRR) and transmission disequilibrium (TDT) in 97 family trios with schizophrenia from SW China. We found no evidence for an excess of longer CAG repeats in the patients, and the ETDT test was not significant for either allele-wise (P = 0.31) or genotype-wise analysis (P = 0.18). However, there was a deficit of transmission of the (CAG)20 repeat allele to affected offspring when this allele was considered individually by TDT (P = 0.012; not corrected for multiple testing). These data do not support a role for larger alleles at the hKCa3 locus in psychosis in Chinese subjects.

Adolescent↗