Many more studies have implicated Kl as an ‘aging’ gene[36,48-53]; it is highly expressed in first the kidney and then the brain in mouse models, and also results in abnormalities such as hypogonadism, ectopic calcification, epidermal atrophy, emphysema, hearing loss, elevated Vitamin D and calcium levels, and neurodegeneration[51]. Here, KL is linked to pulmonary emphysema.