Homozygous individuals

The genetic constitution of an organism, which it has inherited from its parents. The genotype refers to the particular combination of alleles at specified loci present in an organism homozygous individuals have identical alleles and heterozygous individuals have different alleles. 

Ditzel HI, Rosenkilde MM, Garred P, et al. The CCR5 receptor acts as an alloantigen in CCR5Delta32 homozygous individuals identification of chemokine and HIV-1-blocking human antibodies. Proc Natl Acad Sci U S A 1998 95 5241-5245. 

The in vitro data and the results from this clinical trial were synthesized in a so-called dynamic model of receptor kinetics by Liggett [72]. According to this theory, Gly/Gly homozygous individuals are already down-regulated as a result of exposure to endogenous catecholamines. Thus, the recurring exogenous exposure to... 

Homozygous individuals (1/10 ) often have myocardial infarctions before 20 years of age. 

Inactivating LPL mutations lead to a > 60% reduction in LPL activity in postheparin plasma from homozygous individuals [49]. Mutations that result in only reduced LPL enzyme activity usually show less reduction in the activity assay, even in homozygous patients [64]. Heterozygous carriers of a mutation have no reduction in LPL activity and show no clinical signs. 

Inactivating HL mutations lead to basically absent HL activity in postheparin plasma from homozygous individuals [81, 82]. Heterozygous carriers of a HL mutation have intermediate HL activity, which is lower than in normal controls. However, this lower HL activity does not translate into changes in lipoprotein metabolism, leaving these patients with similar lipoprotein profiles to normal controls [81, 82]. 

CBS deficiency is inherited as an autosomal recessive trait. Homozygous individuals (I in 200,000 births) have classical homocystinuria with extremely high plasma tHcy. The 677 C > T polymorphism in MTHFR is believed to be one of the most common causes of mildly elevated plasma tHcy, The frequency of the homozygous genotype is I 1% to 15% in North Americans, 5% to 23% in Europeans, I I % in healthy Japanese populations, and only 2,5% in the Indian population in New Delhi (12-14). The polymorphism induces thermolability in the enzyme, resulting in defect remethylation of... 

ORNL used a factor of 10 for the uncertainty factor to protect susceptible subpopulations (UFh) because some individuals have a genetic polymorphism causing their serum-ChE activity to be abnormally low (Evans et al. 1952 Harris and Whittaker 1962). For homozygous individuals, the activity can be as low as 8-21% of the normal mean (Bonderman and Bonderman 1971). Genetic polymorphisms are also recognized for buty... 

Liu ISC, Seeman P, Sanyal S et al (1996) Dopamine D4 receptor variant in Africans, D (Valine 194Glycine), is insensitive to dopamine and clozapine report of a homozygous individual. Am J Med Genet 61 277-282... 

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