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We describe a mother and her three daughters who all have bilateral congenital dislocation of the hip. The mother has had no other medical problems and is on the 90th centile for height. Her three daughters resemble each other strongly with facial characteristics which include hypertelorism, epicanthic folds, puffiness around the eyes, a flat mid-face and a carp-shaped mouth. All three daughters are on the 3rd centile for height, with their head circumference on a higher centile and all had an ASD. Other features include congenital dislocation of one knee (one), congenital inguinal hernia (one) and vesico-ureteric reflux (one). They also have clinodactyly and hyperextensible finger joints, both features also seen in their father, whose height is on the 3rd centile and who had bilateral congenital inguinal herniae. Collagen studies of skin and ligament were normal. This family does not appear to fit with any of the recognized congenital dislocation syndromes and we suggest that they may represent a previously undescribed syndrome.

Laminin is a basement membrane glycoprotein composed of three nonidentical chains, A, B1, and B2. Variant chains such as merosin and S-laminin have been found in different tissues. We have isolated a cDNA encoding a novel laminin A variant that hybridizes to a 6.45-kb mRNA. Using amplification of genomic DNA and flow-sorted chromosomes we have assigned the gene (LAMA4) for this new laminin A variant to chromosome 6. Fluorescence in situ hybridization of a YAC clone further localized the gene to 6q21.

Muscle biopsy and fibroblast culture of a floppy child with Ehlers-Danlos syndrome type IV were studied. Biochemical analysis of the tissue showed drastically reduced amount of collagen type III. Electron microscopic examination of muscle as well as of cultured fibroblasts showed grossly dilated and dominated the cytoplasm endoplasmic reticulum. Dilatation may result from storage of an abnormal collagen type III molecule. Our observations indicate that type III collagen deficiency may be present clinically as a congenital muscle hypotonia. Specific ultrastructural abnormalities of fibroblasts found in muscle biopsy can enable the proper diagnosis.

The Ehlers-Danlos type IV syndrome is a severe disease with premature death from catastrophic tearing of large arteries and a tendency to intestinal rupture. These patients lack the genetically distinct type III collagen. Here evidence is presented that obligate heterozygotes have lowered levels of type III collagen in their skin and that their cultured fibroblasts produce less than normal amounts of this protein. The inheritance is autosomal recessive.

One of the genetically distinct collagens (type III) normally found in skin, aorta, and intestine is missing from the tissues of patients with the Ehlers-Danlos syndrome type IV. While skin fibroblasts from other individuals synthesize both types I and III collagen. Ehlers-Danlos syndrome IV cells synthesize only type I. These results suggest that the fragile skin, blood vessels, and intestines of Ehlers-Danlos syndrome IV patients result from an absence of type III collagen.

✓ Skin and temporal arterial biopsies were obtained from 17 patients undergoing surgery for ruptured cerebral aneurysm, and specimens were taken from six age- and sex-matched control surgical patients. Radioactively labeled and control tissue collagen patterns were studied by interrupted polyacrylamide gel electrophoresis (PAGE), using the trisborate buffer system or by carboxymethyl cellulose (CMC) chromatography. Type III/I collagen ratios were then measured from autoradiographs of the radioactively labeled samples using the Joyce Loebl gel scanner adapted for flat bed gels. In the case of the CMC labeled material, the ratios were measured by the ratios of the summed radioactively labeled α1(III), α2(II), and α2(I) peaks. Eleven of the 17 patients were Type III collagen-deficient while all of the six control patients had normal collagen ratios. The implications of these findings are discussed.

Skin biopsy specimens from 21 patients with Ehlers-Danlos syndrome (EDS) were compared with controls. With two exceptions, the appearance of the dermal collagen and elastic tissue as seen in the two groups was indistinguishable. One example of type 4 EDS contained a dermis composed of fibers that resembled actinically damaged elastic tissue. The single example of type 6 EDS contained particularly thin collagen fibers. The dermal thickness of specimens of EDS was similar to that of controls, although the abnormal-appearing specimen of type 4 EDS was also abnormally thin. Since the other two biopsy specimens of type 4 appeared to be within the range of normal, there may be heterogeneity in this form of EDS. ( Arch Dermatol 115:40-42, 1979)

Recent clinical examination of 140 British patients with pseudoxanthoma elasticum (PXE) showed both autosomal and recessive inheritance. Fifty-seven recessive families were studied and showed two disease patterns. Patients with type 1 recessive PXE had flexurally distributed rash, moderately severe retinal disease, and a particular predisposition to gastrointestinal bleeding. Type 2 recessive disease is much rarer and affects the entire skin which is loose-fitting, lax, and extensively infiltrated with degenerated elastic fibers. Pooled data for these two groups clearly support an autosomal recessive pattern of inheritance.