Scientific background:

Summary: Laminin beta-2 is an essential component of mature glomerular laminin, which is found in glomerular basement membrane. Homozygous mutations cause congenital nephrotic syndrome, Pierson syndrome.

Molecule: Laminins are large heterotrimer. Glomerular laminin changes its composition after birth. Fetal glomerular laminin, laminin-10, consists of (alpha-5:beta-1:gamma-1) and changes into (alpha-5:beta-2:gamma-1), called laminin-11. The component beta-2 that replaces beta-1 during maturation into laminin-11 is encoded by the LAMB2 gene.

Molecular anatomy: Laminins have important functions in cellular differentiation and adhesion. Laminin-11 is an essential component of the glomerular basement membrane.

Methodology:

	clinical test	Method		Genomic sequencing of the entire coding region
		Turn-around time		20 working days
		Effort		large
		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.

Literature: 

Hasselbacher K et al. (2006) Recessive missense mutations in LAMB2 expand the clinical spectrum of LAMB2-associated disorders.
Zenker M et al. (2004) Human laminin beta2 deficiency causes congenital nephrosis with mesangial sclerosis and distinct eye abnormalities.
Glastre C et al. (1990) Familial infantile nephrotic syndrome with ocular abnormalities.
Farquhar MG et al. (2006) The glomerular basement membrane: not gone, just forgotten.
Zenker M et al. (2004) Human laminin beta2 deficiency causes congenital nephrosis with mesangial sclerosis and distinct eye abnormalities.
Zenker M et al. (2004) Human laminin beta2 deficiency causes congenital nephrosis with mesangial sclerosis and distinct eye abnormalities.