The word allele is a short form of allelomorph (other form, a word coined by William Bateson and Edith Rebecca Saunders), which was used in the early days of genetics to describe variant forms of a gene detected as different phenotypes.
Causes. Male sexual arousal is a complex process that involves the brain, hormones, emotions, nerves, muscles and blood vessels. Erectile dysfunction can result from a problem with any of these. Likewise, stress and mental health concerns can cause or worsen erectile dysfunction.Sometimes a combination of physical and psychological issues causes erectile dysfunction.For instance, a minor physical condition that slows your sexual response might cause anxiety about maintaining an erection.rectile dysfunction can result from a problem with any of these. Likewise, stress and mental health concerns can cause or worsen erectile dysfunction. Sometimes a combination of physical and psychological issues causes erectile dysfunction.
There are many causes of erectile dysfunction (impotence) and some include: 1  blood vessel diseases (such as peripheral vascular disease and others), 2  systemic disease, 3  hormonal imbalance, and. 4  medications (such as blood pressure and heart medications).