The reference OMIM entry for this protein is 107710

Apolipoprotein c-i; apoc1

CLONING

Tata et al. (1985) synthesized a mixed oligonucleotide 17 bases long and used it to isolate cDNA clones for apoC-I from an adult liver cDNA library.

MAPPING

Tata et al. (1985) used a probe and Southern blot techniques to identify the human APOC1 gene in the DNA of various human-rodent cell hybrids. Their results assigned the gene to chromosome 19. By the study of somatic cell hybrids containing rearranged chromosome 19, Scott et al. (1985) concluded that the chromosome 19 cluster of apolipoprotein genes probably lies in the 19p13-19cen region. (HGM8 placed the cluster in the 19cen-19q13 region.) Davison et al. (1986) showed that there are 2 APOC1 sequences on chromosome 19 and that 1 of them is 4 kb 3-prime to apolipoprotein E (APOE; 107741) and oriented in the same way as APOE. One APOC1 gene appeared to be a pseudogene because no mRNA product could be detected in any tissue (Lauer et al., 1988). There are 2 APOC1 mRNA transcripts, but these may be the consequence of differential processing of a single primary transcript. Lusis et al. (1986) used a reciprocal whole arm translocation between the long arm of chromosome 19 and the short arm of chromosome 1 to determine that the APOC1, APOC2, APOE and GPI loci are on the long arm and the LDLR, C3 and PEPD loci on the short arm. They isolated a single lambda phage carrying APOC1 and part of APOE. These genes are 6 kb apart and arranged tandemly. APOC2 and APOE were previously shown to be tightly linked. Studying a cDNA APOC1 clone and a genomic APOE clone, Myklebost and Rogne (1986) concluded that the loci are 4.3 kb apart. By comparison, on chromosome 11, APOA1 (107680) is 2.6 kb from APOC3 (107720). Using separate probes for each locus, Bailey and Miller (1987) mapped APOC2 and APOE to 19q13.1 at the border of q12 by in situ hybridization. Smit et al. (1988) presented a map of the apolipoprotein E-C1-C2 gene cluster on chromosome 19: 5-prime--APOE--4.3 kb--APOC1--6 kb--APOC1 pseudogene--about 22 kb--APOC2--3-prime. Thus, the cluster spans approximately 48 kb. This gene order and the size of the cluster were confirmed by Myklebost and Rogne (1988) by pulsed-field gel electrophoresis mapping methods. A HpaI RFLP in the APOE-C1-C2 gene cluster on chromosome 19 is strongly associated with familial dysbetalipoproteinemia. Smit et al. (1988) showed that this RFLP site is between APOE and APOC1 and specifically that it is located 317 bp upstream of the transcription initiation site of the APOC1 gene. They constructed a detailed restriction map of the gene cluster, showing that the APOC2 gene is located 15 kb downstream of the APOC1 pseudogene. Although Trask et al. (1993) did not map the APOC1 gene directly, the mapping of the APOE and APOC2 genes to 19q13.2 by fluorescence in situ hybridization established that the APOC1 gene is also in this band.

MOLECULAR GENETICS

Age-associated memory impairment (AAMI) is a designation used to define the nondemented elderly with subjective and objective memory impairment presenting no medical or other psychopathologic conditions that could explain the memory problems (Crook et al., 1986). Bartres-Faz et al. (2001) noted that it was controversial whether AAMI described a subgroup of normally aging subjects or, on the other hand, whether these individuals presented particular characteristics distinguishable from controls or an intermediate stage between normal aging and dementia. Because an association between an APOE p ... More on the omim web site

Subscribe to this protein entry history

Oct. 19, 2018: Protein entry updated
Automatic update: OMIM entry 107710 was added.

Oct. 19, 2018: Additional information
Initial protein addition to the database. This entry was referenced in Bryk and co-workers. (2017).