Which autosomal recessive disorder is characterized by a complete absence of HDL?

Tangier disease is characterized by a nearly complete absence of high-density lipoprotein (HDL) in the blood, which is a defining feature of this specific disorder. In Tangier disease, the body does not adequately transport cholesterol and phospholipids due to a mutation in the ATP-binding cassette transporter A1 (ABCA1) gene. This leads to the inability to form HDL particles, which are essential for the transport of cholesterol from peripheral tissues back to the liver.

In contrast, other disorders listed, such as LCAT deficiency, hepatic lipase deficiency, and familial hypoalphalipoproteinemia, may show varying levels of HDL but do not result in its complete absence. For instance, LCAT deficiency affects the maturation of HDL but does not eliminate it entirely, and while hepatic lipase deficiency can impact lipid metabolism, it does not lead to the same level of HDL absence as seen in Tangier disease. Familial hypoalphalipoproteinemia refers to low levels of HDL, but again, it does not imply a complete absence. Thus, the key differentiating factor for Tangier disease is the total lack of HDL, making it the correct answer.