Assembly and Analysis of Cosmid Contigs in the CEA-gene Family Region of Human Chromosome 19

The carcinoembryonic antigen (CEA)-like genes are members of a
large gene family which Is part of the immunoglobulln superfamily.
The CEA family is divided into two major subgroups, the
CEA-subgroup and the pregnancy-specific glycoprotein
(PSG)-subgroup. In the course of an effort to develop a set of
overlapping cosmlds spanning human chromosome 19, we identified 245
cosmids In a human chromosome 19 cosmid library (6 – 7X redundant)
by hybridization with an IgC-like domain fragment of the CEA gene.
A fluorescence-based restriction enzyme digest fingerprinting
strategy was used to assemble 212 probe-positive cosmids, along
with 115 additional cosmids from a collection of ~ 8, 000 randomly
selected cosmids, into five contigs. Two of the contigs contain
CEA-subgroup genes while the remaining three contigs contain
PSG-subgroup genes. These five contigs range in size from 100 kb to
over 300 kb and span an estimated 1 Mb. The CEA-like gene family
was determined by fluorescence in situ hybridization to map in the
q13.1-q13.2 region of human chromosome 19. Analysis of the two
CEA-subgroup contigs provided verification of the contig assembly
strategy and insight into the organization of 9 CEA-subgroup genes.