Globally, urea is the most widely used nitrogen fertilizer and is made accessible to plants via the urease reaction. However, sequence information for the plant enzyme is scarce. A cDNA encoding urease from soybean (Glycine max) has been cloned and sequence information has been obtained for two alleles (11 and 19 kbp, respectively) of the potato (Solanum tuberosum, cv. Desiree) urease gene and ...

PURPOSE. To determine the disease course in Usher syndrome type IB (USH1B) caused by myosin 7A (MYO7A) gene mutations. METHODS. USH1B patients (n = 33, ages 2-61) representing 25 different families were studied by ocular examination, kinetic and chromatic static perimetry, dark adaptometry, and optical coherence tomography (OCT). Consequences of the mutant alleles were predicted. RESULTS. All M...

Cystic fibrosis (CF) is the most common inherited disorder in Caucasian populations, with over 1400 cystic fibrosis transmembrane conductance regulator (CFTR) mutations. The type of mutations and their distributions varies widely between different countries and/or ethnic groups. Seventy Iranian cystic fibrosis patients were screened for the CFTR gene mutation using ARMS/PCR (amplification refra...

BACKGROUND The MC1R gene implicated in melanogenesis and skin pigmentation is highly polymorphic. Several alleles are associated with red hair and fair skin phenotypes and contribute to melanoma risk. OBJECTIVE This work aims to assess the effect of different classes of MC1R variants, notably rare variants, on melanoma risk. Methods. MC1R coding region was sequenced in 1131 melanoma patients ...

Twelve laboratory populations of recently collected Drosophila willistoni were begun with different frequencies of alleles at three enzyme loci, six populations at 25 degrees and six at 19 degrees . Periodic sampling of the populations allowed monitoring of the frequency changes in allozymes over time.-At Lap-5 (a locus coding for leucine amino peptidase), three alleles converged to the same fr...

We determined the common polymorphism of apolipoprotein E (E2, E3, and E4), apolipoprotein B Xba I polymorphism, and apolipoprotein C-III Sst I polymorphism in almost all Finnish centenarians alive in 1991 (n = 179/185). Plasma lipid and lipoprotein levels in different apolipoprotein genotypes were also measured. In comparison with younger Finnish populations studied previously, the frequency o...

N SEVERAL species in which cross-incompatibility is determined by I multiple oppositional alleles, different types of tests have shown that these series of alleles are very extensive. The test yielding the most decisive results and involving the fewest crosses consists of making all possible reciprocal combinations (that is, diallel crosses) between plants which have one S factor in common. Thi...

background: human leukocyte antigens (hla) are polymorphic cell surface proteins. distribution of hla alleles vary among different racial and ethnic populations in unrelated stem cell registries. determination of hla allele frequencies in different ethnic groups is useful for population genetic analyses. materials and methods: based on data available from the iranian stem cell donor registry, h...