Extended Data Fig. 7: Segregation analysis of Fa and Mfa.

a, Genotype data from the JI2822 x JI0816 F₂ population, presented in an Excel spreadsheet format. The F₂ individuals are sorted left to right according to their phenotype and their genotypic scores at Fa and Mfa. In the central upper part of the figure, homozygous JI0816 genotypes (fa/fa) are represented in yellow, homozygous JI2822 genotypes (Fa/Fa) are represented in green, and heterozygotes (Fa/fa) are represented in blue. In the central lower part of the figure, homozygous JI0816 genotypes (Mfa/Mfa) are represented in yellow, homozygous JI2822 genotypes (mfa/mfa) are represented in green, and heterozygotes (Mfa/mfa) are represented in blue. The limits of recombination intervals are marked by horizontal black lines. Wild-type (dark green) and fasciated (orange) phenotype scores are shown above the genotyping data. Homozygous and heterozygous genotypes at a proposed modifier locus, mfa, are shown below the genotyping data. F₂ individuals informative for the positioning of Fa are marked with a red box; b, Tables explaining a one gene model of the summarised numerical data from panel a, where genotype fa/fa is fasciated; c, Tables explaining a two gene model of the summarised numerical data from panel a, showing the postulated Fa Mfa interaction, where the dominant allele Mfa is required for fasciation to occur. In this model fa/fa mfa/mfa is wild type but fa/fa Mfa/_ is fasciated. In both tables the numbers in red are F₂ individuals with unexpected genotype/phenotype combinations, which were further tested and confirmed in the F₃ population (Supplementary Notes and Supplementary Fig. 28).