The genes for all seven of Mendel's traits have now been identified

The seven traits that Gregor Mendel worked with were: seed shape (R/r), cotyledon color (I/i), seed and flower color (A/a), pod shape (V/v), pod color (Gp/gp), flower position (Fa/fa), and stem length (Le/le). The last trait is also known as Tall (T) and short (t).

The genes for four of these traits (seed shape, cotyledon color, flower color, and stem length) were identified and characterized many years ago. The genes for the remaining three traits have now been identified. The results were published in the June 25, 2025 issue of Nature (Feng et al., 2025).

A new higher mutation rate in humans includes indels in repetitive DNA regions

Theme

Mutation

-definition
-mutation types
-mutation rates
-phylogeny
-controversies

There are three ways of estimating the human mutation rate. The Biochemical Method is based on the known error rate of DNA replication and the average number of cell divisions between generations. It gives a rate of about 130 mutations per generation.

The Phylogenetic Method assumes that a large fraction of mammalian genomes is evolving at the neutral rate because it is junk DNA. Since we know that the rate of fixation of neutral alleles is equal to the mutation rate, we can estimate the mutation rate if we know the total number of nucleotide difference between two species (e.g. humans and chimpanzees) and the approximate time of divergence from a common ancestor. This gives an estimate of about 112 mutations per generation.