Final answer:
Werner syndrome is an autosomal recessive disorder characterized by premature aging, caused by mutations in the WRN gene on chromosome 8. This gene encodes a RecQ helicase important for telomere replication. Unlike autosomal dominant disorders, two copies of the abnormal gene are needed to manifest Werner syndrome.
Step-by-step explanation:
People with Werner syndrome, an autosomal recessive disease, show signs of premature aging that begins in adolescence or early adulthood, including wrinkled skin, graying of the hair, baldness, cataracts, and muscle atrophy. The causative gene called WRN has been mapped to human chromosome 8 and normally encodes a RecQ helicase enzyme, which is necessary for the replication of telomeres.
Autosomal recessive inheritance means that the disorder corresponds to the recessive phenotype. Heterozygous individuals, or carriers, will not display symptoms because their one unaffected gene will compensate. This contrasts with autosomal dominant disorders, like Huntington's disease, wherein only one copy of an abnormal gene is necessary for the appearance of the disease. The aging process is associated with telomere shortening, and cells with shorter telomeres can contribute to age-related diseases.