Detection of two polymorphic sites in the human c-fms gene: allele frequency and genotype in some populations of Russia

Two polymorphic sites were found in the human c-fms gene: one (G-->A) was in position 34,047 in the last intron, and the other (dinucleotide TC-->CA) was in positions 34,293 and 34,294 in the 3'-untranslated gene region, 34 bp downstream of the translation stop codon. The polymorphic dinucleotide appeared to be immediately upstream of an octamer showing 100% homology to cis element -CAAACTTC-, which is responsible for controlled instability of mRNAs of several genes. Based on these data, functional significance was assumed for this polymorphism of the c-fms gene. Allele frequencies were established for several populations. The mutant allele of the polymorphism located in the intron were detected only in one family of ethnic Germans from the Altaiskii krai. Polymorphism of the second site, which is in the 3'-untranslated region of the c-fms gene, was observed in all Caucasoid and Mongoloid populations examined. Frequency of the rare allele varied from 19.7-25% in Arctic Mongoloids to 31-42.6% in Central Asian Mongoloids and was similar in two Caucasoid populations (22.6% in ethnic Russians and 26.5% in ethnic Germans). The wide distribution of the mutant allele in human populations of the two races was considered indicative of an adaptive role of the polymorphism in providing a certain level of the gene product, a receptor, in certain cell processes.     

Deletion of the developmentally essential gene ATR in adult mice leads to age-related phenotypes and stem cell loss

Developmental abnormalities, cancer, and premature aging each have been linked to defects in the DNA damage response (DDR). Mutations in the ATR checkpoint regulator cause developmental defects in mice (pregastrulation lethality) and humans (Seckel syndrome). Here we show that eliminating ATR in adult mice leads to defects in tissue homeostasis and the rapid appearance of age-related phenotypes, such as hair graying, alopecia, kyphosis, osteoporosis, thymic involution, fibrosis, and other abnormalities. Histological and genetic analyses indicate that ATR deletion causes acute cellular loss in tissues in which continuous cell proliferation is required for maintenance. Importantly, thymic involution, alopecia, and hair graying in ATR knockout mice were associated with dramatic reductions in tissue-specific stem and progenitor cells and exhaustion of tissue renewal and homeostatic capacity. In aggregate, these studies suggest that reduced regenerative capacity in adults via deletion of a developmentally essential DDR gene is sufficient to cause the premature appearance of age-related phenotypes.     

Detection of Two Polymorphic Sites in the Human c-fms Gene: Allele Frequencies in Several Russian Populations

Two polymorphic sites were found in the human c-fms gene: one (G A) was in position 34047 in the last intron, and the other (dinucleotide TC CA) was in positions 34 293 and 34 294 in the 3"-untranslated gene region, 34 bp downstream of the translation stop codon. The polymorphic dinucleotide appeared to be immediately upstream of an octamer showing 100% homology to cis element –CAAACTTC–, which is responsible for controlled instability of mRNAs of several genes. Based on these data, functional significance was assumed for this polymorphism of the c-fms gene. Allele frequencies were established for several populations. The mutant allele of the polymorphism located in the intron were detected only in one family of ethnic Germans from the Altaiskii krai. Polymorphism of the second site, which is in the 3"-untranslated region of the c-fms gene, was observed in all Caucasoid and Mongoloid populations examined. Frequency of the rare allele varied from 19.7–25% in Arctic Mongoloids to 31–42.6% in Central Asian Mongoloids and was similar in two Caucasoid populations (22.6% in ethnic Russians and 26.5% in ethnic Germans). The wide distribution of the mutant allele in human populations of the two races was considered indicative of an adaptive role of the polymorphism in providing a certain level of the gene product, a receptor, in certain cell processes.