The formation of methylmercaptan from ingested asparagus is a recessive trait. To find out if you are a methylmercaptan forming individual, simply eat a serving of asparagus and wait approximately 20 minutes before urinating. You will be able to detect a very distinctive odor if you have inherited the ability to form methylmercaptan. What percent of the population would be homozygous recessive for this trait if it is known that 30% are homozygous dominant?