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1

Preliminary studies on the inheritance of white coat colour in Arctic foxes (Alopex lagopus L.)

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Filistowicz A., Wierzbicki H., Przysiecki P.

Journal of Applied Genetics

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1997

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vol. 38

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issue 1

57-64

EN

. Main genes determining white coat colour in Arctic foxes are: recessive gene d and incompletely dominant, autosomal gene S with lethal effect in homozygous condition. The white coat colour of Arctic foxes bred on Polish farms had been determined solely by the recessive gene until the 1970s, when the Shadow variety was imported from Norway. The genetic code of the two varieties was different, but this fact was not taken into account. The results obtained in the present study do not confirm the theories on the heredity of white coat colour of Arctic foxes. The authors of these theories assumed that the coat colour depends on the presence of a recessive gene, the only factor responsible for the white furcoat. Apart from Polar and Shadow white foxes, there is a wide variety of darker white animals, and this fact suggests that there is a number of cumulative genes responsible for the intensity of coat pigmentation.

2

Genetic, phenotypic and environmental trends of conformation traits in arctic fox Alopex lagopus (L.)

100%

Wierzbicki H., Filistowicz A., Przysiecki P.

Journal of Applied Genetics

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2000

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vol. 41

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issue 2

113-122

EN

Data on 3782 arctic foxes, bred on a Sniaty fox farm (Poland) in 1985-1998 were used to estimate the genetic, phenotypic and environmental trends of conformation traits. Body size (BS), colour type (CT), colour purity (CP), coat density (CD), hair length (HL), general appearance (GA) and total score (TS) were analysed. The BLUP with a single-trait animal model was used to estimate the genetic trends. The estimates of genetic and phenotypic trends were positive for BS, CT, CP, HL, GA, TS and ranged from 0.0006 to 0.0995 point/year and from 0.0100 to 0.1302 point/year, respectively, but were negative for CD (- 0.0374 point/year and - 0.0262 point/year, respectively). The environmental trends ranged from - 0.0024 point/year for CT to 0.0304 point/year for TS.

3

Statistical aspects of genetic association testing in small samples, based on selective DNA pooling data in the arctic fox

100%

Szyda J., Liu Z., Zaton-Dobrowolska M., Wierzbicki H., Rzasa A.

Journal of Applied Genetics

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2008

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vol. 49

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issue 1

81-92

EN

We analysed data from a selective DNA pooling experiment with 130 individuals of the arctic fox (Alopex lagopus), which originated from 2 different types regarding body size. The association between alleles of 6 selected unlinked molecular markers and body size was tested by using univariate and multinomial logistic regression models, applying odds ratio and test statistics from the power divergence family. Due to the small sample size and the resulting sparseness of the data table, in hypothesis testing we could not rely on the asymptotic distributions of the tests. Instead, we tried to account for data sparseness by (i) modifying confidence intervals of odds ratio; (ii) using a normal approximation of the asymptotic distribution of the power divergence tests with different approaches for calculating moments of the statistics; and (iii) assessing P values empirically, based on bootstrap samples. As a result, a significant association was observed for 3 markers. Furthermore, we used simulations to assess the validity of the normal approximation of the asymptotic distribution of the test statistics under the conditions of small and sparse samples.

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Preliminary studies on the inheritance of white coat colour in Arctic foxes (Alopex lagopus L.)

Genetic, phenotypic and environmental trends of conformation traits in arctic fox Alopex lagopus (L.)

Statistical aspects of genetic association testing in small samples, based on selective DNA pooling data in the arctic fox