The association of serum lipoprotein(a) levels, apolipoprotein(a) size and (TTTTA)(n) polymorphism with coronary heart disease.
BACKGROUND
The association between lipoprotein(a) levels, apolipoprotein(a) size and the (TTTTA)(n) polymorphism which is located in the 5' non-coding region of the apo(a) gene was studied in 263 patients with severe coronary heart disease and 97 healthy subjects.


METHODS
Lp(a) levels were measured by ELISA, apo(a) isoform size was determined by SDS-agarose gel electrophoresis, and analysis of the (TTTTA)(n) was carried out by PCR. For statistical calculation, both groups were divided into low (at least one apo(a) isoform with < or = 22 Kringle IV) and high (both isoforms with >22 KIV) apo(a) isoform sizes, and into low number (<10 in both alleles) and high number of (> or =10 at least one allele) TTTTA repeats.


RESULTS
Lp(a) levels were higher (P=0.007), apo(a) isoforms size < or =22 KIV and TTTTA repeats > or = 10 were more frequent (P=0.007 and 0.01) in cases than in controls. Lp(a) levels were found to be increased with low apo(a) weight in both groups (both P<0.0001). In multivariate logistic regression analysis, only the Lp(a) levels (P=0.005) and (TTTTA)(n) polymorphism (P=0.002) were found to be significantly associated with CHD.


CONCLUSIONS
Nevertheless, these results indicate that in CHD patients the (TTTTA)(n) polymorphism has an effect on Lp(a) levels which is independent of the apo(a) size.
Kalina A
Cardiology Department, MAV Hospital, 1014 Tancsics M.20, Budapest, Hungary. kalinaak@mail.matav.hu
Császár
A
A
Füst
G
G
Nagy
B
B
Szalai
C
C
Karádi
I
I
Duba
J
J
Prohászka
Z
Z
Horváth
L
L
Dieplinger
H
H
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001053:Apolipoproteins / Q000097:blood* / Q000737:chemistry / Q000235:genetics*; D053241:Apoprotein(a); D003327:Coronary Disease / Q000097:blood* / Q000235:genetics*; D005260:Female; D006801:Humans; D017270:Lipoprotein(a) / Q000097:blood* / Q000737:chemistry / Q000235:genetics*; D008297:Male; D018895:Microsatellite Repeats / Q000235:genetics; D008875:Middle Aged; D015999:Multivariate Analysis; D011110:Polymorphism, Genetic / Q000235:genetics*; D020033:Protein Isoforms / Q000737:chemistry; D012016:Reference Values
D001053:Apolipoproteins; D017270:Lipoprotein(a); D020033:Protein Isoforms; D053241:Apoprotein(a)