• Genomics & Informatics
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• 제10권2호
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• pp.117-122
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• 2012

A sample size with sufficient statistical power is critical to the success of genetic association studies to detect causal genes of human complex diseases. Genome-wide association studies require much larger sample sizes to achieve an adequate statistical power. We estimated the statistical power with increasing numbers of markers analyzed and compared the sample sizes that were required in case-control studies and case-parent studies. We computed the effective sample size and statistical power using Genetic Power Calculator. An analysis using a larger number of markers requires a larger sample size. Testing a single-nucleotide polymorphism (SNP) marker requires 248 cases, while testing 500,000 SNPs and 1 million markers requires 1,206 cases and 1,255 cases, respectively, under the assumption of an odds ratio of 2, 5% disease prevalence, 5% minor allele frequency, complete linkage disequilibrium (LD), 1:1 case/control ratio, and a 5% error rate in an allelic test. Under a dominant model, a smaller sample size is required to achieve 80% power than other genetic models. We found that a much lower sample size was required with a strong effect size, common SNP, and increased LD. In addition, studying a common disease in a case-control study of a 1:4 case-control ratio is one way to achieve higher statistical power. We also found that case-parent studies require more samples than case-control studies. Although we have not covered all plausible cases in study design, the estimates of sample size and statistical power computed under various assumptions in this study may be useful to determine the sample size in designing a population-based genetic association study.

• Asian-Australasian Journal of Animal Sciences
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• 제31권8호
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• pp.1098-1102
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• 2018

Objective: Temperament can be defined as a type of behavioral tendency that appears in a relatively stable manner in responses to various external stimuli over time. The aim of this study was to estimate genetic parameters for the records of temperament testing that are used to improve the temperament of Jeju crossbred (Jeju${\times}$Thoroughbred) horses. Methods: This study was conducted using 205 horses (101 females and 104 males) produced between 2010 and 2015. The experimental animals were imprinted and tamed according to the Manual for Horse Taming and Evaluation for Therapeutic Riding Horses and evaluated according to the categories for temperament testing (gentleness, patience, aggressiveness, sensitivity, and friendliness) between 15 months and 18 months of age. Each category was scored on a five-point linear scale. Genetic parameters for the test categories were analyzed using a multi-trait mixed model with repeated records. The ASReml program was used to analyze the data. Results: The heritability of gentleness, patience, aggressiveness, sensitivity and friendliness ranged from 0.08 to 0.53. The standard errors of estimated heritability ranged from 0.13 to 0.17. The test categories showed high genetic correlations with each other, ranging from 0.96 to 0.99 and high repeatability, ranging from 0.70 to 0.73. Conclusion: The results of this study showed that the test categories had moderate heritability and high genetic correlations, but additional studies may be necessary to use the results for the improvement programs of the temperament of Jeju crossbred horses.

• Molecules and Cells
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• 제19권3호
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• pp.428-435
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• 2005

This study was carried out to assess the potential of SSR markers for variety identification by comparing SSR markers and morphological traits in tests of distinctiveness, uniformity, and stability (DUS) of pepper (Capsicum annuum L.) varieties. Twenty-seven SSR markers were polymorphic in 66 pepper varieties, revealing a total of 89 alleles. Average polymorphism information content (PIC) value was 0.529, ranging from 0.03 to 0.877. Cluster analysis of the band patterns separated the varieties into three groups corresponding to varietal types. Morphological trait-based clustering showed some degree of similarity to dendrogram topologies based on the SSR index. However, no significance correlation was found between the SSR and morphological data. SSR markers could be used to complement a DUS test of a candidate variety and to select complimentary varieties by pre-screening existing varieties in the context of protecting new varieties of pepper.

• Clinical and Experimental Reproductive Medicine
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• 제48권4호
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• pp.283-294
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• 2021

A genetic etiology of male infertility is identified in fewer than 25% of infertile men, while 30% of infertile men lack a clear etiology, resulting in a diagnosis of idiopathic male infertility. Advances in reproductive genetics have provided insights into the mechanisms of male infertility, and a characterization of the genetic basis of male infertility may have broad implications for understanding the causes of infertility and determining the prognosis, optimal treatment, and management of couples. In a substantial proportion of patients with azoospermia, known genetic factors contribute to male infertility. Additionally, the number of identified genetic anomalies in other etiologies of male infertility is growing through advances in whole-genome amplification and next-generation sequencing. In this review, we present an up-to-date overview of the indications for appropriate genetic tests, summarize the characteristics of chromosomal and genetic diseases, and discuss the treatment of couples with genetic infertility by microdissection-testicular sperm extraction, personalized hormone therapy, and in vitro fertilization with pre-implantation genetic testing.

• Journal of Interdisciplinary Genomics
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• 제3권1호
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• pp.13-20
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• 2021

Developmental and epileptic encephalopathies are the most devastating early-onset epilepsies, characterized by early-onset seizures that are often intractable, electroencephalographic abnormalities, developmental delay or regression, and various comorbidities. A large number of underlying genetic variants of developmental and epileptic encephalopathies have been identified over the past few decades. However, the most thorough sequencing studies leave 60-65% of patients without a molecular diagnosis. This review explores the genetic basis of developmental and epileptic encephalopathies that start within the first year of life, including Ohtahara syndrome, early myoclonic encephalopathy, epilepsy of infancy with migrating focal seizures, infantile spasms, and Dravet syndrome. The purpose of this review is to give an overview and encourage the clinicians to start considering genetic testing as an important investigation along with electroencephalogram for better understanding and management of developmental and epileptic encephalopathies.

• Journal of Genetic Medicine
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• 제19권2호
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• pp.57-62
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• 2022

Systemic autoinflammatory diseases (SAIDs) are characterized by unprovoked inflammatory episodes such as recurrent/periodic fever, serositis, skin lesions, abdominal symptoms, arthritis/arthralgia, and central nervous system involvement. Genetic diagnosis of SAIDs has been challenging because disease manifestations overlap among themselves and with other immunological disease categories, such as infection and autoimmune diseases. However, the advent of next-generation sequencing (NGS) technologies and expanding knowledge about the innate immunity and inflammation have made the routine genetic diagnosis of SAIDs possible. Here, we review the recurrent/periodic fevers, other recently identified autoinflammatory diseases, and type I interferonopathies, and discuss the clinical usefulness of NGS targeted sequencing for SAIDs, and recent advance of understandings for this heterogeneous disease group as for underlying primary immunodeficiency.

• Journal of Genetic Medicine
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• 제21권1호
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• pp.1-5
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• 2024

Despite advances in the diagnosis and management of rare diseases (RDs), there remains a tendency to overlook adult RD patients. In addition to the considerable number of adult-onset RDs, advances in the diagnosis and management of pediatric RDs have led to an increase in the survival of these patients into adulthood. Adult RDs exhibit distinct features from pediatric counterparts, necessitating careful consideration during medical assessments. Given the extended life expectancy of adult RD patients, precise diagnosis and management strategies can significantly enhance patient outcomes. This review aims to provide an in-depth exploration of the characteristics unique to adult RDs. Special emphasis will be placed on the importance of cascade screening and prenatal genetic testing in the context of adult RDs, highlighting the need for a comprehensive understanding of these aspects in clinical practice.

• Clinical and Experimental Reproductive Medicine
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• 제51권2호
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• pp.91-101
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• 2024

Infertility is a complex disease characterized by extreme genetic heterogeneity, compounded by various environmental factors. While there are exceptions, individual genetic and genomic variations related to infertility are typically rare, often family-specific, and may serve as susceptibility factors rather than direct causes of the disease. Consequently, identifying the cause of infertility and developing prevention and treatment strategies based on these factors remain challenging tasks, even in the modern genomic era. In this review, we first examine the genetic and genomic variations associated with infertility, and subsequently summarize the concepts and methods of preimplantation genetic testing in light of advances in genome analysis technology.

• Clinical and Experimental Pediatrics
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• 제50권9호
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• pp.835-840
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• 2007

Any infant noted to be jaundiced at 2 weeks of age should be evaluated for cholestasis with measurement of total and direct serum bilirubin. With the insight into the clinical phenotype and the genotype-phenotype correlations, it is now possible to evaluate more precisely the neonate who presents with conjugated hyperbilirubinemia. Testing should be performed for the specific treatable causes of neonatal cholestasis, specifically sepsis, galactosemia, tyrosinemia, citrin deficiency and endocrine disorders. Biliary atresia must be excluded. Low levels of serum gamma-glutamyl transferase in the presence of cholestasis should suggest progressive familial intrahepatic cholestasis type 1, 2, or arthrogryposis- renal dysfunction-cholestasis syndrome. If the serum bile acid level is low, a bile acid synthetic defect should be considered. Molecular genetic testing and molecular-based diagnostic strategies are in evolution.

• Asian-Australasian Journal of Animal Sciences
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• 제25권11호
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• pp.1511-1514
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• 2012

Epistasis that may explain a large portion of the phenotypic variation for complex economic traits of animals has been ignored in many genetic association studies. A Baysian method was introduced to draw inferences about multilocus genotypic effects based on their marginal posterior distributions by a Gibbs sampler. A simulation study was conducted to provide statistical powers under various unbalanced designs by using this method. Data were simulated by combined designs of number of loci, within genotype variance, and sample size in unbalanced designs with or without null combined genotype cells. Mean empirical statistical power was estimated for testing posterior mean estimate of combined genotype effect. A practical example for obtaining empirical statistical power estimates with a given sample size was provided under unbalanced designs. The empirical statistical powers would be useful for determining an optimal design when interactive associations of multiple loci with complex phenotypes were examined.