An incomplete enumeration algorithm for an exact test of Hardy–Weinberg proportions with multiple alleles

2007 ◽  
Vol 115 (3) ◽  
pp. 393-398 ◽  
Author(s):  
H. P. Maurer ◽  
A. E. Melchinger ◽  
M. Frisch
Keyword(s):  
Enumeration Algorithm ◽  
Multiple Alleles ◽  
Exact Test

scholarly journals Multi-allelic Exact tests for Hardy-Weinberg equilibrium that account for gender

2017 ◽  
Author(s):  
Jan Graffelman ◽  
Bruce Weir
Keyword(s):  
Permutation Test ◽  
Statistical Tests ◽  
Enumeration Algorithm ◽  
Test Procedures ◽  
Allelic Variants ◽  
Multiple Alleles ◽  
Exact Test ◽  
Weinberg Equilibrium ◽  
Hardy Weinberg Equilibrium ◽  
And Gender

Statistical tests for Hardy-Weinberg equilibrium are important elementary tools in genetic data analysis. X-chromosomal variants have long been tested by applying autosomal test procedures to females only, and gender is usually not considered when testing autosomal variants for equilibrium. Recently, we proposed specific X-chromosomal exact test procedures for bi-allelic variants that include the hemizygous males, as well as autosomal tests that consider gender. In this paper we present the extension of the previous work for variants with multiple alleles. A full enumeration algorithm is used for the exact calculations of tri-allelic variants. For variants with many alternate alleles we use a permutation test. Some empirical examples with data from the 1000 genomes project are discussed.

scholarly journals A network algorithm for the X chromosomal exact test for Hardy-Weinberg equilibrium with multiple alleles

2020 ◽  
Author(s):  
Jan Graffelman ◽  
Leonardo Ortoleva
Keyword(s):  
Permutation Test ◽  
Statistical Methodology ◽  
Enumeration Algorithm ◽  
Test Procedures ◽  
Multiple Alleles ◽  
Exact Test ◽  
Weinberg Equilibrium ◽  
Network Algorithm ◽  
Hardy Weinberg Equilibrium ◽  
Chromosomal Variants

AbstractStatistical methodology for testing Hardy-Weinberg equilibrium at X chromosomal variants has recently experienced considerable development. Up to a few years ago, testing X chromosomal variants for equilibrium was basically done by applying autosomal test procedures to females only. At present, male alleles can be taken into account in asymptotic and exact test procedures for both the bi- and multiallelic case. However, current X chromosomal exact procedures for multiple alleles rely on a classical full enumeration algorithm and are computationally expensive, and in practice not feasible for more than three alleles. In this article we extend the autosomal network algorithm for exact Hardy-Weinberg testing with multiple alleles to the X chromosome, achieving considerable reduction in computation times for multiallelic variants with up to five alleles. The performance of the X-chromosomal network algorithm is assessed in a simulation study. Beyond four alleles, a permutation test is, in general, the more feasible approach. A detailed description of the algorithm is given and examples of X chromosomal indels and microsatellites are discussed.

Performing the Exact Test of Hardy-Weinberg Proportion for Multiple Alleles

Biometrics ◽  
1992 ◽  
Vol 48 (2) ◽  
pp. 361 ◽  
Author(s):  
Sun Wei Guo ◽  
Elizabeth A. Thompson
Keyword(s):  
Multiple Alleles ◽  
Exact Test

An Exact Test for Hardy-Weinberg and Multiple Alleles

Biometrics ◽  
1987 ◽  
Vol 43 (4) ◽  
pp. 805 ◽  
Author(s):  
Edward J. Louis ◽  
Everett R. Dempster
Keyword(s):  
Multiple Alleles ◽  
Exact Test

Venous Thromboembolism and High Grade Gliomas

1993 ◽  
Vol 70 (03) ◽  
pp. 393-396 ◽  
Author(s):  
Mandeep S Dhami ◽  
Robert D Bona ◽  
John A Calogero ◽  
Richard M Hellman
Keyword(s):  
Risk Factors ◽  
Venous Thromboembolism ◽  
Medical Center ◽  
Significant Risk ◽  
Bleeding Complications ◽  
Fisher Exact Test ◽  
High Grade ◽  
Chi Square ◽  
Exact Test ◽  
High Grade Gliomas

SummaryA retrospective study was done to determine the incidence of and the risk factors predisposing to clinical venous thromboembolism (VTE) in patients treated for high grade gliomas. Medical records of 68 consecutive patients diagnosed and treated at Saint Francis Hospital and Medical Center from January 1986 to June 1991 were reviewed. The follow up was to time of death or at least 6 months (up to December 1991). All clinically suspected episodes of VTE were confirmed by objective tests. Sixteen episodes of VTE were detected in 13 patients for an overall episode rate of 23.5%. Administration of chemotherapy (p = 0.027, two tailed Fisher exact test) and presence of paresis (p = 0.031, two tailed Fisher exact test) were statistically significant risk factors for the development of VTE. Thrombotic events were more likely to occur in the paretic limb and this difference was statistically significant (p = 0.00049, chi square test, with Yates correction). No major bleeding complications were seen in the nine episodes treated with long term anticoagulation.We conclude that venous thromboembolic complications are frequently encountered in patients being treated for high grade gliomas and the presence of paresis and the administration of chemotherapy increases the risk of such complications.

Isolated Liner Revision for Total Knee Arthroplasty Instability: A Road That Should Remain Less Taken

2020 ◽  
Author(s):  
Jason D. Tegethoff ◽  
Rafael Walker-Santiago ◽  
William M. Ralston ◽  
James A. Keeney
Keyword(s):  
Total Knee Arthroplasty ◽  
Femoral Component ◽  
Knee Arthroplasty ◽  
Primary Total Knee Arthroplasty ◽  
P Value ◽  
Surgical Morbidity ◽  
Exact Test ◽  
Total Knee ◽  
Component Revision

AbstractIsolated polyethylene liner exchange (IPLE) is infrequently selected as a treatment approach for patients with primary total knee arthroplasty (TKA) prosthetic joint instability. Potential advantages of less immediate surgical morbidity, faster recovery, and lower procedural cost need to be measured against reoperation and re-revision risk. Few published studies have directly compared IPLE with combined tibial and femoral component revision to treat patients with primary TKA instability. After obtaining institutional review board (IRB) approval, we performed a retrospective comparison of 20 patients treated with IPLE and 126 patients treated with tibial and femoral component revisions at a single institution between 2011 and 2018. Patient demographic characteristics, medical comorbidities, time to initial revision TKA, and reoperation (90 days, <2 years, and >2 years) were assessed using paired Student's t-test or Fisher's exact test with a p-value <0.01 used to determine significance. Patients undergoing IPLE were more likely to undergo reoperation (60.0 vs. 17.5%, p = 0.001), component revision surgery (45.0 vs. 8.7%, p = 0.002), and component revision within 2 years (30.0 vs. 1.6%, p < 0.0001). Differences in 90-day reoperation (p = 0.14) and revision >2 years (p = 0.19) were not significant. Reoperation for instability (30.0 vs. 4.0%, p < 0.001) and infection (20.0 vs. 1.6%, p < 0.01) were both higher in the IPLE group. IPLE does not provide consistent benefits for patients undergoing TKA revision for instability. Considerations for lower immediate postoperative morbidity and cost need to be carefully measured against long-term consequences of reoperation, delayed component revision, and increased long-term costs of multiple surgical procedures. This is a level III, case–control study.

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