Domestic dogs evolved from ancestral gray wolves. Wolves have coats of short, straight hair and lack 'furnishings,' a growth pattern marked by eyebrows and a mustache found in some domestic dogs. In domestic dogs, coat variation is controlled by allelic variation in three genes. Recessive mutant alleles in the FGF5 gene result in long hair, while dogs carrying the dominant ancestral allele have short hair. Likewise, recessive mutant alleles in the KRT71 gene result in curly hair, whereas dogs with an ancestral dominant allele have straight hair. Dominant mutant alleles in the RSPO2 gene cause the presence of furnishings, while dogs homozygous for the ancestral recessive allele have no furnishings. A pure-breeding curly- and long-haired poodle with furnishings was crossed to a pure-breeding short- and straight-haired border collie lacking furnishings

What are the genotypes and phenotypes of the puppies?

Key Concepts

Genotype and Phenotype

Genotype refers to the genetic makeup of an organism, specifically the alleles it carries for a particular trait. Phenotype, on the other hand, is the observable physical or biochemical characteristics of an organism, which result from the interaction of its genotype with the environment. Understanding the distinction between these two concepts is crucial for predicting the traits of offspring based on parental genotypes.

Alleles and Dominance

Alleles are different forms of a gene that can exist at a specific locus on a chromosome. In genetics, dominance describes the relationship between alleles, where a dominant allele can mask the expression of a recessive allele. This concept is essential for determining the phenotypes of the offspring, as the presence of dominant alleles will influence the traits expressed in the puppies.

Punnett Square

A Punnett square is a diagram used to predict the genotypes and phenotypes of offspring from a genetic cross. By organizing the alleles from each parent, it allows for a visual representation of the possible combinations that can occur in the offspring. This tool is particularly useful in this scenario to determine the potential genotypes and phenotypes of the puppies resulting from the cross between the poodle and the border collie.