Introduction Genetics is the science of how traits are passed from one generation to another. Turkey color genetics questions are common on this site, and some people have asked for a guide to color genetics. Hopefully this thread will be a useful reference. I will create another thread called "Turkey Genetics Feedback" where you can ask questions, complain, correct inaccuracies, or boo me off the stage. Please use the feedback thread for comments so people dont have to look to hard to find a topic they may be interested in. There are still some genetic combinations that I don't fully appreciate yet, and I will stay away from these or simply say I dont know (another chance to provide feedback). I will start with a brief discussion of basic genetics, then talk about the standard bronze, then discuss how different colors are produced by deviating from the bronze. My vision is that by the end of this series, everyone will know how to cross different strains to intentionally raise any color of turkey they want. So, here we go. Lesson 1. Basic Genetics To understand how turkey colors are determined, we need to start with a basic understanding of genetics. Genetics is the study of how traits (such as eye color in people) are passed from one generation to the next. This next section will introduce a lot of terminology. You will not have to remember all the terms to understand color determination, but it is presented here for background. This will be the longest, hardest, and least interesting of the lessons, but will help you to understand future lessons. I have presented a summary in advance to help you know where we are going. Summary Genes are found at particular spots on chromosomes called loci (plural of locus). There are two genes that define every trait. One gene came from the father and one from the mother. Genes usually come in dominant recessive allele pairs. Dominant alleles (genes) express themselves even if only one dominant gene is present. Dominant traits get capital letters, such as B, while recessive traits get lower case of the same letter, b. There may be more than two alleles for a given trait. Dominance may be incomplete. A gene is a part of a strand of DNA. Genes are strung together into long strands of DNA called chromosomes. Chromosomes are paired, and each half of the pair of each chromosome has a set of genes for the same traits. In other words, if one half of a chromosome has genes for eye color, hair color, and skin pigment, then the other half of that chromosome also has genes for eye color, hair color, and skin pigment. One strand of each chromosome comes from each parent. The location of a gene on the chromosome is called the locus. The genetic information for eye color in people is always at the same location on the same chromosome. It is always at the same locus. The form of the gene is called an allele. Again, for human eye color, there are two basic alleles, one for blue eyes and one for brown eyes. The alleles are not always the same. If one parent has two alleles for brown eyes, and one parent has two alleles for blue eyes, the offspring will all have one brown eye allele and one blue eye allele. The term allele is often replaced with the word gene. Most genes come in dominant/recessive pairs. In other words, there are two possible alleles for any one locus, and one is dominant over the other. It expresses itself even when both alleles are present. For human eye color, brown eye genes are dominant to blue eye genes, so people with one brown gene and one blue gene have brown eyes, just like people with two brown genes. Only people with two blue genes have blue eyes. Dominant recessive pairs are usually written with using the same letter, with the dominant gene capitalized. So B is used for brown eye genes, and b is used for blue eye genes. Someone with two brown eye genes would be describes as BB, and someone with two blue eyed genes would be described as bb. These combinations are called homozygous (two of the same allele). Someone with one of each would be described as Bb (heterozygous, meaning two different alleles). Eye color is nice and simple because there are only two alleles, and one is completely dominant to the other. Some genes have more than two alleles, and there may be a chain of dominance, like a pecking order. The next lesson will have a turkey example involving three possible alleles at a locus. Also, dominance is not always complete. For example, if you cross a red snapdragon with a white snapdragon, you get a pink snapdragon. In this case, the red flower is RR (red gene, red gene), the white flower is rr (not red, not red), and the pink flower is Rr (red, not red). With incomplete dominance, one red gene and one not red gene makes the flower half red, or pink. Incomplete dominance will come up later. I think this will be enough to get us started. Summary Genes are found at particular spots on chromosomes called loci (plural of locus). There are two genes that define every trait. One gene came from the father and one from the mother. Genes usually come in dominant recessive pairs. Dominant genes express themselves even if only one dominant gene is present. There may be more than two genes for a given trait. Dominance may be incomplete.