• Journal of applied mathematics & informatics
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• v.10 no.1_2
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• pp.111-118
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• 2002

We study the influence of observations on testing a linear hypothesis using single and multiple case-deletions. The change in the F-test statistic due to case-deletions is shown to be completely determined by two externally Studentized residuals. These residuals we used for investigating the outlyingness when there are linear constraints or not. An illustrative example is given. It shows the usefulness of case-deletions.

• Journal of Genetic Medicine
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• v.18 no.2
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• pp.110-116
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• 2021

Microdeletions of chromosome 22q11.2 are one of the most common microdeletions occurring in humans, and is known to be associated with a wide range of highly variable features. These deletions occur within a cluster of low copy repeats (LCRs) in 22q11.2, referred to as LCR22 A-H. DiGeorge (DGS)/velocardiofacial syndrome is the most prevalent form of a 22q11.2 deletions, caused by mainly proximal deletions between LCR22 A and D. As deletions of distal portion to the DGS deleted regions has been extensively studied, the recurrent distal 22q11.2 microdeletions distinct from DGS has been suggested as several clinical entities according to the various in size and position of the deletions on LCRs. We report a case of long-term follow-up of a female diagnosed with a 22q11.2 distal deletion syndrome, identified a deletion of 1.9 Mb at 22q11.21q11.23 (chr22: 21,798,906-23,653,963) using single nucleotide polymorphism array. This region was categorized as distal deletion type of 22q11.2, involving LCR22 D-F. She was born as a preterm, low birth weight to healthy non-consanguineous Korean parents. She showed developmental delay, growth retardation, dysmorphic facial features, and mild skeletal deformities. The patient underwent a growth hormone administration due to growth impairment without catch-up growth. While a height gain was noted, she had become overweight and was subsequently diagnosed with pre-diabetes. Our case could help broaden the genetic and clinical spectrum of 22q11.2 distal deletions.

• Communications for Statistical Applications and Methods
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• v.20 no.3
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• pp.217-223
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• 2013

Two influence diagnostic methods for the common mean model are proposed. First, an investigation of the influence of observations according to minor perturbations of the common mean model is made by adapting the local influence method which is based on the likelihood displacement. It is well known that the maximum likelihood estimates are in general sensitive to influential observations. Case-deletions can be a candidate for detecting influential observations. However, the maximum likelihood estimators are iteratively computed and therefore case-deletions involve an enormous amount of computations. An approximation by Newton's method to the maximum likelihood estimator obtained after a single observation was deleted can reduce much of computational burden, which will be treated in this work. A numerical example is given for illustration and it shows that the proposed diagnostic methods can be useful tools.

• Communications for Statistical Applications and Methods
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• v.23 no.3
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• pp.231-239
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• 2016

A graphical diagnostic method based on multiple case deletions in a regression context is introduced by using the sampling distribution of the difference between two least squares estimators with and without multiple cases. Principal components analysis plays a key role in deriving this diagnostic method. Multiple case deletions of test statistic are also considered when a new observation is fitted to a given regression model. The result is useful for detecting influential observations in econometric data analysis, for example in checking whether the consumption pattern at a later time is the same as the one found before or not, as well as for investigating the influence of cases in the usual regression model. An illustrative example is given.

• Communications for Statistical Applications and Methods
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• v.21 no.3
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• pp.253-260
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• 2014

The intraclass correlation model has a long history of applications in several fields of research. Case deletion diagnostic methods for the intraclass correlation model are proposed. Based on the likelihood equations, we derive a formula for a case deletion diagnostic method which enables us to investigate the influence of observations on the maximum likelihood estimates of the model parameters. Using the Taylor series expansion we develop an approximation to the likelihood distance. Numerical examples are provided for illustration.

• Clinical and Experimental Pediatrics
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• v.58 no.8
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• pp.313-316
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• 2015

Interstitial deletions involving the chromosome band 15q22q24 are very rare and only nine cases have been previously reported. Here, we report on a 12-day-old patient with a de novo 15q22q23 interstitial deletion. He was born by elective cesarean section with a birth weight of 3,120 g at 41.3-week gestation. He presented with hypotonia, sensory and neural hearing loss, dysmorphism with frontal bossing, flat nasal bridge, microretrognathia with normal palate and uvula, thin upper lip in an inverted V-shape, a midline sacral dimple, severe calcanovalgus at admission, and severe global developmental delay at 18 months of age. Fluorescence in situ hybridization findings confirmed that the deleted regions contained at least 15q22. The chromosome analysis revealed a karyotype of 46,XY,del(15) (q22q23). Parental chromosome analysis was performed and results were normal. After reviewing the limited literature on interstitial 15q deletions, we believe that the presented case is the first description of mapping of an interstitial deletion involving the chromosome 15q22q23 segment in Korea. This report adds to the knowledge of the clinical phenotype associated with the 15q22q23 deletion.

• Clinical and Experimental Reproductive Medicine
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• v.31 no.2
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• pp.105-110
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• 2004

Objectives: Despite severe oligospermia, males with Y chromosome microdeletion can achieve conception through ICSI (Intracytoplasmic Sperm Injection). However, ICSI may not only result in the transmission of microdeletions but also the expansion of deletion to the offspring. The purpose of this study was to screen vertical transmission, expansion of microdeletions and de novo deletion in male fetuses conceived by ICSI. Materials and Methods: A total of 32 ICSI treated patients with their 33 (a case of twin) male fetuses conceived by ICSI were used to make this study group. Sequence-tagged sites (STSs)-based PCR analyses were performed on genomic DNA isolated from peripheral blood of fathers and from the amniocytes of male fetuses. Ten primer pairs namely, sY134, sY138, MK5, sY152, sY147, sY254, sY255, SPGY1, sY269 and sY158 were used. The samples with deletions were verified at least three times. Results: We detected a frequency of 12.5% (4 of the 32 patients) of microdeletions in ICSI patients. In 4 patients with detected deletions, two patients have proven deletions on single STS marker and their male fetuses have the identical deletion in this region. Another two patients have two and three deletions, but their male fetuses have more than 3 deletions which include deletions to their father's. Meanwhile, seven male fetuses, whose fathers were analyzed to have all 10 STS markers present, have deletions present in at least one or more of the markers. Conclusions: Although the majority of deletions on the Y chromosome are believed to arise de novo, in some cases a deletion has been transmitted from the fertile father to the infertile patient. In other cases the deletion was transmitted through ICSI treatment, it is likely that one sperm cell is injected through the oocyte's cytoplasm and fertilization can be obtained from spermatozoa. Our tests for deletion were determined by PCR and our results show that the ICSI treatment may lead to vertical transmission, expansion and de novo Y chromosome microdeletions in male fetuses. Because the sample group was relatively small, one should be cautious in analyzing these data. However, it is important to counsel infertile couples contemplating ICSI if the male carries Y chromosomal microdeletions.

• Molecules and Cells
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• v.19 no.1
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• pp.114-123
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• 2005

Nitropyrene, the predominant nitropolycyclic hydrocarbon found in diesel exhaust, is a mutagenic and tumorigenic environmental pollutant that requires metabolic activation via nitroreduction and ring oxidation. In order to determine the role of ring oxidation in the mutagenicity of 1-nitropyrene, its oxidative metabolites, 1-nitropyrene 4,5-oxide and 1-nitropyrene 9,10-oxide, were synthesized and their mutation spectra were determined in the coding region of hprt gene of CHO cells by a PCR amplification of reverse-transcribed hprt mRNA, followed by a DNA sequence analysis. A comparison of the two metabolites for mutation frequencies showed that 1-nitropyrene 9,10-oxide was 2-times higher than 1-nitropyrene 4,5-oxide. The mutation spectrum for 1-nitropyrene 4,5-oxide was base substitutions (33/49), one base deletions (11/49) and exon deletions (5/49). In the case of 1-nitropyrene 9,10-oxide, base substitutions (27/50), one base deletions (15/50), and exon deletions (8/50) were observed. Base substitutions were distributed randomly throughout the hprt gene. The majority of the base substitutions in mutant from 1-nitropyrene 4,5-oxide treated cells were $A{\rightarrow}G$ transition (15/33) and $G{\rightarrow}A$ transition (8/33). The predominant base substitution, $A{\rightarrow}G$ transition (11/27) and $G{\rightarrow}A$ transition (8/27), were also observed in mutant from 1-nitropyrene 9,10-oxide treated cells. The mutation at the site of adenine and guanine was consistent with the previous results, where the sites of DNA adduct formed by these compounds were predominant at the sites of purines. A comparison of the mutational patterns between 1-nitropyrene 4,5-oxide and 1-nitropyrene 9,10-oxide showed that there were no significant differences in the overall mutational spectrum. These results indicate that each oxidative metabolite exhibits an equal contribution to the mutagenicity of 1-nitropyrene, and ring oxidation of 1-nitropyrene is an important metabolic pathway to the formation of significant lethal DNA lesions.

• Communications for Statistical Applications and Methods
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• v.9 no.2
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• pp.473-478
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• 2002

A test for a single outlier in multivariate regression with linear constraints on regression coefficients using a mean shift model is derived. It is shown that influential observations based on case-deletions in testing linear hypotheses are determined by two types of outliers that are mean shift outliers with or without linear constraints, An illustrative example is given.

• Clinical and Experimental Pediatrics
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• v.59 no.sup1
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• pp.19-24
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• 2016

Constitutional interstitial deletions of the long arm of chromosome 5 (5q) are quite rare, and the corresponding phenotype is not yet clearly delineated. Severe mental retardation has been described in most patients who present 5q deletions. Specifically, the interstitial deletion of chromosome 5q33.3q35.1, an extremely rare chromosomal aberration, is characterized by mental retardation, developmental delay, and facial dysmorphism. Although the severity of mental retardation varies across cases, it is the most common feature described in patients who present the 5q33.3q35.1 deletion. Here, we report a case of a de novo deletion of 5q33.3q35.1, 46,XY,del(5)(q33.3q35.1) in an 11-year-old boy with mental retardation; to the best of our knowledge this is the first case in Korea to be reported. He was diagnosed with severe mental retardation, developmental delay, facial dysmorphisms, dental anomalies, and epilepsy. Chromosomal microarray analysis using the comparative genomic hybridization array method revealed a 16-Mb-long deletion of 5q33. 3q35.1(156,409,412-172,584,708)x1. Understanding this deletion may help draw a rough phenotypic map of 5q and correlate the phenotypes with specific chromosomal regions. The 5q33.3q35.1 deletion is a rare condition; however, accurate diagnosis of the associated mental retardation is important to ensure proper genetic counseling and to guide patients as part of long-term management.