We test the hypothesis that polymorphisms of the brain regulator genes MCPH1 and ASPM contribute to variations in human brain size and its correlates. We measured general mental ability, head circumference and social intelligence in 644 Canadian adults (496 Caucasians, 36 Orientals, 84 Mixed Race/Other and 28 Blacks; 257 men and 387 women). The gene polymorphisms were assessed from buccal DNA; ...

Rosai-Dorfman disease (sinus histiocytosis with massive lymphadenopathy) is a benign systemic proliferative disorder of histiocytes resembling the sinus histiocytes of lymph nodes. The typical clinical features of this disease include bilateral painless lymphadenopathy, fever, and polyclonal hyperglobulinaemia. The condition may present with extranodal involvement in 43% of cases, and cutaneous...

The prevalence of methane production in an adult population of 256 subjects was 41%, but it was significantly higher in females (49%), than males (33%). When the population was subdivided into ethnic groups. Caucasians (48%) and Black (45%) had significantly more methane producers than Orientals (24%) and Indians (32%). when the ethnic groups were analysed by sex, female Caucasians had the high...

Naevus of Ota (naevus fusculocoeruleus ophthalmomaxillaris) was described by the Japanese dermatologist, Ota, in 1939 as a dermal melanocytic hamartoma that presents as bluish hyperpigmentation along the ophthalmic, maxillary, and mandibular branches of the trigeminal nerve. It is bilateral in less than 5% cases, occurring frequently in Orientals (0.2%–1%) and darker races and rarely in white p...

Thyrotoxic periodic paralysis (TPP) is rare in non-Orientals, and sporadic case reports were reported world-wide. Eight cases were reported in Arabs, including 3 Saudis. We present an additional case of TPP in a 38-year-old Saudi man, and review the literature on TPP in Arabs. Our patient presented with complete flaccid quadriplegia, 5 weeks after he was diagnosed with Graves' disease that was ...

Polymorphism of human C'3 has been defined by prolonged agarose electrophoresis of fresh serum. At least four, and probably five, alleles have been identified by the electrophoretic mobilities of gene products. Inheritance of three alleles, F(1) F, and S, is consistent with the autosomal condominant type. The inheritance of S(1) is probably codominant and that of F(0.8) is not known. Of the 15 ...

K eloids and Hypertrophic scars (HSc) are dermal fibroproliferative disorders unique to humans that occur following trauma, inflammation, surgery, burns and sometimes spontaneously. These are characterized by excesses deposition of collagen in the dermis and the subcutaneous tissues. Contrary to the fine­ line scar characteristics of normal wound repair, the exuberant scarring of keloid and HSc...

Many Orientals lack the mitochondrial aldehyde dehydrogenase (ALDH2) activity responsible for the oxidation of acetaldehyde produced during ethanol metabolism. These individuals suffer the alcohol-flush reaction when they drink alcoholic beverages. The alcohol-flush reaction is the result of excessive acetaldehyde accumulation, and the unpleasant symptoms tend to reduce alcohol consumption. The...

Results of genealogical, DNA, and clinical findings in 41 families with 235 patients affected with myotonic dystrophy (DM) led to the following observations. (1) The relative proportion of affected patients among blacks is apparently lower than among whites or orientals. (2) A significant excess of males was observed. (3) The frequency of DM patients who did not reproduce was similar for males ...