PHYLOGEOGRAPHIC ANALYSIS OF THE BROODING BRITTLE STAR AMPHIPHOLIS SQUAMATA (ECHINODERMATA) ALONG THE COAST OF NEW ZEALAND REVEALS HIGH CRYPTIC GENETIC VARIATION AND CRYPTIC DISPERSAL POTENTIAL

AbstractA fundamental question in medical genetics is how the genetic background modifies the phenotypic outcome of mutations. We address this question by focusing on the seam cells, which display stem cell properties in the epidermis of Caenorhabditis elegans. We demonstrate that a putative null mutation in the GATA transcription factor egl-18, which is involved in seam cell fate maintenance, is more tolerated in the CB4856 isolate from Hawaii than the lab reference strain N2 from Bristol. We identify multiple quantitative trait loci (QTLs) underlying the difference in phenotype expressivity between the two isolates. These QTLs reveal cryptic genetic variation that reinforces seam cell fate through potentiating Wnt signalling. Within one QTL region, a single amino acid deletion in the heat shock protein HSP-110 in CB4856 is sufficient to modify Wnt signalling and seam cell development, highlighting that natural variation in conserved heat shock proteins can shape phenotype expressivity.

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Descriptive and illustrated diagnosis of Ophiuroidea fauna (Echinodermata) in the shallow waters of North-eastern Brazil

Marine Biodiversity Records ◽

10.1017/s1755267215000652 ◽

2015 ◽

Vol 8 ◽

Author(s):

Fabilene Gomes Paim ◽

Maria Cecília Guerrazzi ◽

Michela Borges

Keyword(s):

Brittle Star ◽

Shallow Waters ◽

Bottom Substrate ◽

Eastern Brazil ◽

North Eastern ◽

Amphipholis Squamata ◽

Biological Substrates ◽

Almost All ◽

First Time ◽

Ophiocoma Echinata

In this study, we present descriptions, illustrations, comments, and bathymetric and geographic distributions of the brittle star species related to the estuary region of Camamu Bay, located in the State of Bahia, Brazil. The brittle star fauna lives on biological substrates, sand bottoms, mud and rubble in the Camamu Bay and comprises 12 species divided into five families. Almost all of them are common in the tropical and subtropical fauna of the regions of shallow water.Ophiophragmus filograneusis reported for the first time in Bahia, and nine other species are recorded for the first time in Camamu Bay:Amphipholis januarii, Amphipholis squamata, Ophiophragmus filograneus, Ophiostigma isocanthum,Ophioderma cinerea, Ophioderma januarii, Ophiactis lymani, Ophiactis savignyi andOphiocoma echinata.The results suggest that the ophiuroid assemblages are strongly affected by marine currents as well as by different kinds of bottom substrate.

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Contribution of trans regulatory eQTL to cryptic genetic variation in C. elegans

BMC Genomics ◽

10.1186/s12864-017-3899-8 ◽

2017 ◽

Vol 18 (1) ◽

Cited By ~ 110

Author(s):

Basten L. Snoek ◽

Mark G. Sterken ◽

Roel P. J. Bevers ◽

Rita J. M. Volkers ◽

Arjen van’t Hof ◽

...

Keyword(s):

Genetic Variation ◽

Cryptic Genetic Variation ◽

C Elegans

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Estimating the heritability of butterfat production

The Journal of Agricultural Science ◽

10.1017/s0021859600049236 ◽

1961 ◽

Vol 57 (3) ◽

pp. 289-294 ◽

Cited By ~ 6

Author(s):

S. R. Searle

Keyword(s):

Genetic Variation ◽

New Zealand ◽

Dairy Cows ◽

Total Variance ◽

Additive Effects ◽

Narrow Sense ◽

Sampling Errors ◽

Gene Effects ◽

Additive Gene Effects ◽

Additive Gene

Part of the variation among butterfat yields in dairy cows arises from genetic differences among the animals. The proportion which this bears to the total variance is known as heritability. In the ‘narrow’ sense it is defined (Lush, 1940), as the proportion of the total variance that is due to additive gene effects; the ‘broad’ sense definition includes genetic variation arising from non-additive gene effects as well as that due to additive effects. Since related animals have a proportion of their genes in common the covariance among their production records can be used for estimating genetic variation and hence heritability. This paper discusses three groups of related animals most frequently used for this purpose, twins, daughter-dam pairs and paternal half-sibs, and presents the results of analysing production records of artificially bred heifers in New Zealand, including evidence of the magnitude of the sampling errors of the heritability estimates.

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