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M H Breuning

Publications and source records attributed to M H Breuning.

148 records · Page 9Linked to original sources

Partial trisomy 6p due to familial translocation t(6;20)(p21;p13). A new syndrome?

Cytogenetic findings in a case of partial trisomy 6p due to a translocation t(6;20)(p21;p13) and eleven balanced translocation heterozygotes are described. The clinical data of the proposita are compared with those of five other published cases. A partial trisomy 6p syndrome is postulated, characterized by: low birth weight, psychomotor retardation, craniofacial abnormalities (such as high prominent forehead, large fontanel, wide sagittal suture, blepharoptosis, low-set and/or malformed ears), congenital heart malformation, small kidneys, and proteinuria. Linkage studies have shown that the breakpoint in chromosome 6 involved in this translocation is close to the HLA gene cluster.

Abnormalities, Multiple↗

Localization of HLA on the short arm of chromosome 6.

A detailed marker gene study in a large Dutch kindred segregating for a reciprocal translocation between the chromosomes 6 and 20, t(6;20) (p21; p13), revealed a close linkage between the HLA genes and the breakpoint on the short arm of 6. During this study an apparent peak lod score of 2.9 was obtained at a recombination value of 0.05 for a linkage between HLA and the breakpoint, indicating that the chromosomal region, carrying the HLA genes, is situated near the breakpoint in band 6p21 close to the transition to 6p22.

Abnormalities, Multiple↗

A highly polymorphic DNA marker linked to adult polycystic kidney disease on chromosome 16.

Adult polycystic kidney disease (APCKD) is a common and often lethal multi-organ disease with an autosomal dominant pattern of inheritance; approximately 1 in 1,000 people carry the mutant gene. The major pathological abnormality is the development and progressive enlargement of cysts in several organs including the liver, pancreas and spleen as well as the kidneys. The basic biochemical defect which leads to the formation of cysts remains unknown. Cyst development, which is not retarded by any known therapy, leads to irreversible renal failure and death at a mean age of 51 unless dialysis or transplantation are used. Patients with the disease account for 9% of chronic dialysis requirement. The first symptoms tend to occur in the fourth decade, after most patients have reproduced. Presymptomatic diagnosis depends on the ultrasonographic detection of cysts, but exclusion cannot be achieved by this means; 34% of at-risk patients in the second decade and 14% in the third will go on to develop cysts after negative diagnosis. The low sensitivity of diagnostic techniques in this critical age-range imposes severe limitations on genetic counselling and the condition cannot be identified prenatally. Hence we have searched for a linkage marker for APCKD; we show here that the APCKD locus is closely linked to the alpha-globin locus on the short arm of chromosome 16 (zeta = 25.85, theta = 0.05).

Chromosomes, Human, 16-18↗