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Titolo: A simulation study of the effects of assignment of prior identitybydescent probabilities to unselected sib pairs, in covariancestructure modeling of a quantitativetrait locus
Autore: Dolan, CV; Boomsma, DI; Neale, MC;
 Indirizzi:
 Univ Amsterdam, Fac Psychol, NL1018 WB Amsterdam, Netherlands Univ Amsterdam Amsterdam Netherlands NL1018 WB B Amsterdam, Netherlands Vrije Univ Amsterdam, Dept Psychol, Amsterdam, Netherlands Vrije Univ Amsterdam Amsterdam Netherlands chol, Amsterdam, Netherlands Virginia Commonwealth Univ, Virginia Inst Psychiat & Behav Genet, Richmond, Virginia Commonwealth Univ Richmond VA USA hiat & Behav Genet, Richmond,
 Titolo Testata:
 AMERICAN JOURNAL OF HUMAN GENETICS
fascicolo: 1,
volume: 64,
anno: 1999,
pagine: 268  280
 SICI:
 00029297(199901)64:1<268:ASSOTE>2.0.ZU;2K
 Fonte:
 ISI
 Lingua:
 ENG
 Soggetto:
 LINKAGE ANALYSIS; POWER; BEHAVIOR; TWIN;
 Tipo documento:
 Article
 Natura:
 Periodico
 Settore Disciplinare:
 Clinical Medicine
 Life Sciences
 Citazioni:
 26
 Recensione:
 Indirizzi per estratti:
 Indirizzo: Dolan, CV Univdsmsterdam, Fac Psychol, Roetersstr 15, NL1018 WB Amsterdam, Netherlan Univ Amsterdam Roetersstr 15 Amsterdam Netherlands NL1018 WB n



 Citazione:
 C.V. Dolan et al., "A simulation study of the effects of assignment of prior identitybydescent probabilities to unselected sib pairs, in covariancestructure modeling of a quantitativetrait locus", AM J HU GEN, 64(1), 1999, pp. 268280
Abstract
Sib pairselection strategies, designed to identify the most informative sib pairs in order to detect a quantitativetrait locus (QTL), give rise to a missingdata problem in genetic covariancestructure modeling of QTL effects. After selection, phenotypic data are available for all sibs, but marker dataand, consequently, the identitybydescent (IBD) probabilitiesare available only in selected sib pairs. One possible solution to this missingdata problem is to assign prior IBD probabilities (i,e., expected values) to the unselected sib pairs. The effect of this assignment in genetic covariancestructure modeling is investigated in the present paper. Two maximumlikelihood approaches to estimation are considered, the pihat approach and the LEDmixture approach. In the simulations, sample size, selection criteria, QTLincreaser allele frequency, and gene action are manipulated. The results indicate that the assignment of prior IBD probabilities results in serious estimation bias in the pihat approach. Bias is also present in the LEDmixture approach, although here the bias is generally much smaller. The null distribution of the loglikelihood ratio (i.e., in absence of any QTL effect) does not follow the expected null distribution in the pihat approach after selection. In the LEDmixture approach, the null distribution doesagree with expectation.
ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 22/01/20 alle ore 09:20:19