Article

Amphibian malformations and inbreeding.

Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA.
Biology letters (impact factor: 3.76). 08/2008; 4(5):549-52. DOI:10.1098/rsbl.2008.0233 pp.549-52
Source: PubMed

ABSTRACT Inbreeding may lead to morphological malformations in a wide variety of taxa. We used genetic markers to evaluate whether malformed urodeles were more inbred and/or had less genetic diversity than normal salamanders. We captured 687 adult and 1,259 larval tiger salamanders (Ambystoma tigrinum tigrinum), assessed each individual for gross malformations, and surveyed genetic variation among malformed and normal individuals using both cytoplasmic and nuclear markers. The most common malformations in both adults and larvae were brachydactyly, ectrodactyly and polyphalangy. The overall frequency of adults with malformations was 0.078 compared to 0.081 in larval samples. Genetic diversity was high in both normal and malformed salamanders, and there were no significant difference in measures of inbreeding (f and F), allele frequencies, mean individual heterozygosity or mean internal relatedness. Environmental contaminants or other extrinsic factors may lead to genome alternations that ultimately cause malformations, but our data indicate that inbreeding is not a causal mechanism.

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Keywords

1,259 larval tiger salamanders
 
allele frequencies
 
causal mechanism
 
Environmental contaminants
 
extrinsic factors
 
genome alternations
 
gross malformations
 
inbred
 
inbreeding
 
internal relatedness
 
larvae
 
larval samples
 
measures
 
normal
 
normal individuals
 
normal salamanders
 
nuclear markers
 
polyphalangy
 
taxa
 
wide variety