Worldwide frequency of a common genetic variant of luteinizing hormone: an international collaborative research. International Collaborative Research Group.
OBJECTIVE
To determine the worldwide frequency of a common immunological LH variant because of two point mutations in the LH beta-subunit gene (Trp8Arg and Ile15Thr).


METHODS
Cross-sectional study on LH status (variant and wild-type) in serum (or DNA) samples from Finland (Finns and Lapps), Estonia, Poland, Sweden, The Netherlands, United Kingdom, Italy, South Africa (blacks), Thailand, China, Japan, and the United States (Hispanics and blacks).


METHODS
Academic research environment.


METHODS
Ambulatory adult men and women (n = 2,936) with minor illnesses and no known endocrinological disorders.


METHODS
A single blood sample was collected from each subject.


METHODS
The LH status was determined by two immunofluorometric assays using monoclonal antibodies. One (assay 1) only recognizes the wild-type LH, the other (assay 2) recognizes equally variant and wild-type LH. The ratio of assay 1 to assay 2 indicates the LH status: wild-type, > 0.9; heterozygote, 0.2 to 0.9; and homozygote, < 0.15. One population (Lapps) was studied by DNA analysis using polymerase chain reaction and allele-specific oligonucleotide hybridization.


RESULTS
The carrier frequency of the variant LH beta allele varied from 7.1% in U.S. Hispanics to 41.9% in Lapps of northern Finland. The variant LH beta allele tended to be more common in populations from Northern Europe as compared with those from Asia.


CONCLUSIONS
The high frequency of the LH beta variant worldwide makes it an important confounding factor when obtaining disproportionately low LH levels with some immunometric assays. The LH variant may contribute to some pathologies of the pituitary-gonadal function.
Nilsson
C
C
Department of Biotechnology, University of Turku, Finland.
Pettersson
K
K
Millar
R P
RP
Coerver
K A
KA
Matzuk
M M
MM
Huhtaniemi
I T
IT
D000293:Adolescent; D000328:Adult; D000483:Alleles; D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal; D001483:Base Sequence; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000737:chemistry; D017931:DNA Primers; D015342:DNA Probes; D005006:Ethnicity; D005260:Female; D005455:Fluorescent Antibody Technique; D014644:Genetic Variation; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007391:International Cooperation; D007986:Luteinizing Hormone / Q000097:blood / Q000737:chemistry / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012727:Sex Characteristics
D000911:Antibodies, Monoclonal; D018997:Chorionic Gonadotropin, beta Subunit, Human; D017931:DNA Primers; D015342:DNA Probes; D007986:Luteinizing Hormone