Scientific background:

Summary: The protein encoded by this gene is involved in LDL receptor binding. Mutations are rare and cause hypercholesterolemia. Autosomal recessive hypercholesterolemia is a bit confusing term because all the mutations causing hypercholesterolemia exert their dose dependent influence.

Methodology:

	clinical test	Method		Genomic sequencing of the entire coding region
		Turn-around time		25 working days
		Effort		little
		Specimen		DNA
		Quality assessment		Internal quality control only
	All known and new missense, nonsense and splice mutations can be detected.
	clinical test	Method		Carrier testing
		Turn-around time		5 working days
		Effort		little
		Specimen		DNA
		Quality assessment		Internal quality control only
	The test is only specific about the mutation already known in this kindred.
	research test	Method		Gene dosage measurements
		Turn-around time		25 working days
		Effort		little
		Specimen		DNA
		Quality assessment		Internal quality control only
	Of the gene rearrangements, this method is useful to detect large deletions or duplications.

Literature: 

Michaely P et al. (2004) The modular adaptor protein ARH is required for low density lipoprotein (LDL) binding and internalization but not for LDL receptor clustering in coated pits.
Nagai M et al. (2003) The adaptor protein ARH escorts megalin to and through endosomes.
Mishra SK et al. (2002) The autosomal recessive hypercholesterolemia (ARH) protein interfaces directly with the clathrin-coat machinery.
He G et al. (2002) ARH is a modular adaptor protein that interacts with the LDL receptor, clathrin, and AP-2.