This domain is known as the HYR (Hyalin Repeat) domain, after the protein hyalin that is composed exclusively of this repeat. This domain probably corresponds to a new superfamily in the immunoglobulin fold. The function of this domain is uncertain it may be involved in cell adhesion [1].

1: HYR, an extracellular module involved in cellular adhesion and related to the immunoglobulin-like fold. Callebaut I, Gilges D, Vigon I, Mornon JP; Protein Sci 2000;9:1382-1390. PMID:10933504