Are the nail-patella syndrome and the autosomal Goltz-like syndrome the phenotypic expressions of different alleles at the COL5A1 locus?

The association of Buschke-Ollendorf syndrome and nail-patella syndrome

Buschke-Ollendorf syndrome and nail-patella syndrome are both rare connective tissue disorders inherited in an autosomal dominant pattern and characterized by cutaneous and bone lesions. We describe a 3-year-old boy and his family who showed clinical features of both Buschke-Ollendorf syndrome and nail-patella syndrome. To our knowledge, this association has not been reported previously, suggesting that these two connective tissue disorders may share the same gene location with different mutations or involve different mutated genes that share downstream segments of their signaling pathways. Furthermore, this young patient is also affected by a chronic idiopathic neutropenia usually not observed in Buschke-Ollendorf syndrome or nail-patella syndrome.

Electronmicroscopic observation of the basement membrane zone in focal dermal hypoplasia

A 3-month-old boy had reticulated achromic and atrophic skin lesions on the right buttock and thigh, as well as partial syndactyly of the third and fourth toes of the right foot. With hematoxylin and eosin stain, an epidermal defect, abnormally located fat cell lobules, and absence of the upper and midportions of the dermis were observed, conforming to a typical histopathologic picture of focal dermal hypoplasia. Electron microscopic examination of the atrophic site showed loose collagen bundles, collagen fibers with loss of regular bands, abnormal fibroblasts, and disruption of the basement membrane zone. These defects in the basement membrane zone strongly suggest that abnormal formation of type IV collagen is associated with focal dermal hypoplasia, and that this abnormal formation of collagen is correlated with the clinical sign of skin atrophy.

A new biallelic DNA polymorphism of the human COL5A1 gene

A cDNA probe of the human COL5A1 gene detects a frequent biallelic PstI polymorphism. Allele A has a frequency of 54% whereas that of allele B is 46%. This restriction fragment length polymorphism provides a useful marker for linkage analysis in 9q34.3.