Genes aren't the only factor. Because you inherit one APOE gene from your mother and another from your father, you have two copies of the APOE gene. Having at least one APOE e4 gene increases your risk of developing Alzheimer's disease. If you have two APOE e4 genes, your risk is even higher.
Compound Time Signatures In compound time signatures, the beat occurs on a dotted note and is divisible by three. The most common compound time signatures are 6/8, 9/8 12/8.
Basics of Meter. meter is a recurring pattern of stresses or accents that provide the pulse or beat of music. Meter is notated at the beginning of a composition with a time signature. Time signatures are always notated with two numbers, one on top of the other, much like a fraction in math. The top number denotes the number of beats in each measure. The bottom number denotes the note value that receives the beat.