For a common trait, prevalence is easily estimated from a random sample of the population. However, this is prohibitively expensive for a rare disease, which is often ascertained through probands [1].

In general, humans have the same genes. A number of genes are varied. These control our physical traits and health. Each variation is called an allele. You inherit two alleles for each gene. One comes ...

This is a shout out to the biologists out there: do you think the concept of dominance and recessive is worthwhile? In other words, does it help in conceptualization more than it hurts? Clearly the ...

Your genes code for all your traits. Some genes are dominant and expressed if you receive a copy from one parent. Others are recessive and only apparent if you receive a copy from both parents. Genes ...

Females have two X chromosomes (XX). Males have one X and one Y chromosome (XY). All eggs contain one X chromosome. Half of sperm contain one X chromosome and half contain one Y chromosome. A mother ...