Dominant ER Stress-Inducing WFS1 Mutations Underlie a Genetic Syndrome of Neonatal/Infancy-Onset Diabetes, Congenital Sensorineural Deafness, and Congenital Cataracts

Neonatal diabetes is frequently part of a complex syndrome with extrapancreatic features: 18 genes causing syndromic neonatal diabetes have been identified to date. There are still patients with neonatal diabetes who have novel genetic syndromes. We performed exome sequencing in a patient and his unrelated, unaffected parents to identify the genetic etiology of a syndrome characterized by neonatal diabetes, sensorineural deafness, and congenital cataracts. Further testing was performed in 311 patients with diabetes diagnosed before 1 year of age in whom all known genetic causes had been excluded. We identified 5 patients, including the initial case, with three heterozygous missense mutations in WFS1 (4/5 confirmed de novo). They had diabetes diagnosed before 12 months (2 before 6 months) (5/5), sensorineural deafness diagnosed soon after birth (5/5), congenital cataracts (4/5), and hypotonia (4/5). In vitro studies showed that these WFS1 mutations are functionally different from the known recessive Wolfram syndrome-causing mutations, as they tend to aggregate and induce robust endoplasmic reticulum stress. Our results establish specific dominant WFS1 mutations as a cause of a novel syndrome including neonatal/infancy-onset diabetes, congenital cataracts, and sensorineural deafness. This syndrome has a discrete pathophysiology and differs genetically and clinically from recessive Wolfram syndrome.

HLA associations of systemic lupus erythematosus in Chinese from Singapore

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Effects of propranolol and oxprenolol on the vasoconstrictor response to noradrenaline in the superficial hand vein in man

The effects of oxprenolol and propranolol on the venoconstrictor response to noradrenaline were studied in healthy volunteers by measuring superficial dorsal hand vein diameter at a standard congesting pressure. In 8 subjects dose response curves to noradrenaline (20-1280 ng/ml) were obtained with noradrenaline alone, with noradrenaline plus propranolol 10 microgram/ml, with noradrenaline plus propranolol 10 microgram/ml plus oxprenolol 3 microgram/ml and with noradrenaline plus propranolol 13 microgram/ml according to a double blind balanced randomised design. Propranolol 10 microgram/ml significantly (p less than 0.05) potentiated the vasoconstrictor response to noradrenaline and the addition of oxprenolol significantly (P less than 0.05) reversed the potentiation giving a response similar to that seen with noradrenaline alone. The higher concentration of propranolol did not produce further potentiation, the response being similar to that obtained with the lower concentration of propranolol. It is suggested that the effect of oxprenolol may be attributable to alpha blocking properties, to partial beta agonism or to its membrane stabilising properties.