Alternative titles; symbols
HGNC Approved Gene Symbol: AHSG
Cytogenetic location: 3q27.3 Genomic coordinates (GRCh38): 3:186,613,060-186,621,318 (from NCBI)
| Location | Phenotype |
Phenotype MIM number |
Inheritance |
Phenotype mapping key |
|---|---|---|---|---|
| 3q27.3 | ?Alopecia-intellectual disability syndrome 1 | 203650 | Autosomal recessive | 3 |
The AHSG gene encodes a multifunctional phosphorylated extracellular calcium-regulatory glycoprotein that has an important role in multiple physiologic processes (summary by Reza Sailani et al., 2017).
Anderson and Anderson (1977) applied the 2-D electrophoretic technique of O'Farrell (O'Farrell, 1975) to the analysis of human plasma proteins. Genetic variants involving charge or size 'should be routinely detectable in at least 20 proteins at once.' About 30 polypeptides were identified, including alpha-2HS-glycoprotein (alpha-2-Heremans-Schmid glycoprotein). The authors recognized 3 phenotypes reflecting 2 autosomal, about equally frequent, codominant alleles. Using polyacrylamide gel isoelectric focusing with immunofixation, Umetsu et al. (1984) described a polymorphism of alpha-2-HS-glycoproteins with 3 common phenotypes designated AHS1-1, AHS2-1 and AHS2-2. Cox and Andrews (1983) used silver stain immunofixation to demonstrate 3 codominant alleles.
A2HS is one of the few 'negative' acute-phase reactants of human plasma. It promotes endocytosis, has opsonic properties, and, because of its high affinity for calcium, probably plays some role in the metabolism of bone where it is concentrated up to 300-fold relative to other plasma proteins. The concentration of AHSG in bone falls progressively throughout childhood to adult life. A2HS consists of 2 polypeptide chains termed A and B. The amino acid sequence of the longer A chain was determined by Yoshioka et al. (1986) and the amino acid sequence and carbohydrate sequence of the shorter B chain were reported by Gejyo et al. (1983).
Lee et al. (1987) showed that the A and B chains of AHSG are encoded by a single gene.
In search of the human homolog for pp63, a phosphorylated rat hepatic glycoprotein that inhibits insulin receptor tyrosine kinase, Srinivas et al. (1993) isolated a DNA clone from a human liver gamma-gt11 cDNA library. DNA sequence analysis revealed identity with the mRNA product of the AHSG gene; the amino acid sequences of AHSG and pp63 showed 70% identity, including complete conservation of the cysteine residues. Northern blot analysis demonstrated a 1.8-kb mRNA in human liver and a hepatoma cell line.
The product of the AHSG gene is commonly referred to as fetuin in species other than the human (Jahnen-Dechent, 1998). Terkelsen et al. (1998) described the distribution of protein and mRNA in embryonic and neonatal rat tissues. The first fetal plasma protein to be described was fetuin, which was purified from fetal and newborn calf serum by Pedersen (1944). Fetuin was subsequently shown to be a very abundant plasma protein in fetal cattle, sheep, pig, and goat, and also to be present in humans and rodents.
Using Northern blot analysis, Denecke et al. (2003) showed that fetuin A and B (FETUB; 605954) transcripts were expressed predominantly in human liver, with lower levels in placenta. Mouse fetuin A and B also showed predominant expression in liver. Immunoblot analysis demonstrated that fetuin A and B were secreted into sera of human, rat, and mouse. Fetuin A and B proteins had apparent molecular masses of 60 kD, higher than the calculated molecular masses, likely due to N-glycosylation and other posttranslational modifications.
Eiberg et al. (1984) found linkage of A2HS with pseudocholinesterase-E1 (BCHE; 177400)--maximum male lod = 5.02 at theta = 0.10 and with transferrin (TF; 190000). In their data, TF and BCHE showed peak male lod = 2.21 at theta = 0.24. The only positive lod score with the centromere of chromosome 3, which from evidence skimpy at that time was thought to carry the TF-BCHE linkage group, was with TF--0.47 at theta 0.23. They proposed that the order is cen--TF--BCHE--A2HS. From studies in a large Hutterite kindred, Zelinski et al. (1987) concluded that the order of the 3 loci is AHSG-TF-BCHE. From study of a child with a duplication of chromosome 3, Cox et al. (1984) concluded that the AHSG locus is located in the 3cen-q13 segment.
Cox and Francke (1985) used hybrids of human fetal liver and rat hepatoma cells to study the location of the genes for serum proteins. In this way they gave direct assignment of the orosomucoid gene to chromosome 9 and the alpha-2-HS-glycoprotein gene to chromosome 3, these having been previously assigned by linkage to 'anchor' loci.
Lee et al. (1987) used the AHSG cDNA to map the gene to 3q21-qter by analysis of human-mouse somatic cell hybrids. By in situ hybridization, Magnuson et al. (1988) narrowed the assignment to 3q27-q29.
While constructing a contig in the 3q27 region, Rizzu and Baldini (1995) identified 2 YAC clones that were positive for the polymorphic marker D3S1602. One was also positive for a sequence tagged site (STS) derived from the kininogen gene (KNG; 612358). Because of the known evolutionary and structural relationship of KNG to other members of the cystatin gene superfamily, they tested the physical linkage of AHSG, KNG, and histidine-rich glycoprotein (HRG; 142640), all of which were previously mapped to 3q. The results showed colocalization of the 3 genes to 2 independent, partially overlapping YAC clones within approximately 1 Mb of DNA. Fluorescence in situ hybridization confirmed the location of the 2 YAC clones to 3q27.
Denecke et al. (2003) mapped the Fetua and Fetub genes to mouse chromosome 13.
Osawa et al. (1997) determined that the coding region of the AHSG gene spans approximately 8.2 kb and contains 7 exons. The 5-prime promoter region contains several characteristic sequences such as an A/T-rich sequence, C/EBP-binding site, and hepatocyte nuclear factor-5 (HNF5) and serum response factor (SRF; 600589) sites.
Srinivas et al. (1993) found that AHSG purified from human serum specifically inhibited insulin-stimulated autophosphorylation of the insulin receptor (INSR; 147670) in vitro and in vivo; AHSG also inhibited insulin-induced tyrosine phosphorylation of insulin receptor substrate-1 (IRS1; 147545) and the association of IRS1 with the p85 subunit of phosphatidylinositol-3 kinase (PIK3R1; 171833) in hepatoma cells. AHSG did not compete with insulin for binding to INSR. Srinivas et al. (1993) concluded that human AHSG functions to regulate insulin action at the insulin receptor tyrosine kinase level.
Denecke et al. (2003) showed that recombinant mouse fetuin A and B inhibited precipitation of basic calcium phosphate, although fetuin B was less active than fetuin A.
Data on gene frequencies of allelic variants were tabulated by Roychoudhury and Nei (1988).
Eiberg et al. (1984) studied the AHSG system by means of 1-dimensional isoelectric focusing combined with immunofixation on cellulose acetate strips. In the Danish population, 2 frequent alleles, S and F, with frequencies of 0.357 and 0.635, respectively, and a rare allele, R, with frequency 0.008, were recognized. Umetsu et al. (1988) reported the polymorphism of AHSG in a population in the Philippines.
Boutin et al. (1985) estimated the frequency of the alleles HSGA1 and HSGA2 (their symbology) to be 0.65 and 0.35, respectively.
To identify the molecular basis of the 2 common AHSG alleles, AHSG*1 and AHSG*2, Osawa et al. (1997) sequenced AHSG cDNA obtained by RT-PCR from polyadenylated RNA of 7 liver tissue samples. Nucleotide substitutions of C-to-T at amino acid position 230 (thr230met; 138680.0001) and C-to-G at position 238 (thr238ser; 138680.0002) were common among samples exhibiting phenotypes 2-1 or 2. Since these substitutions were expected to give rise to an NlaIII site and a SacI site, respectively, for the potential AHSG*2, Osawa et al. (1997) analyzed these substitutions by PCR-RFLP using genomic DNA of 68 individuals. The results were consistent with the IEF analysis of the corresponding serum, indicating that AHSG*1 is characterized by ACG (thr) at position 230 in exon 6 and ACC (thr) at position 238 in exon 7, and that AHSG*2 is characterized by ATG (met) at position 230 and AGC (ser) at position 238.
Alopecia-Intellectual Disability Syndrome 1
In 7 affected members of a large consanguineous Iranian family with alopecia-intellectual disability syndrome-1 (APMR1; 203650), Reza Sailani et al. (2017) identified a homozygous missense mutation in the AHSG gene (R317H; 138680.0004). The mutation, which was found by whole-exome sequencing and confirmed by Sanger sequencing, segregated with the disorder in the family. The mutation was predicted to alter posttranslational protein phosphorylation, and Western blot analysis and immunoprecipitation studies of serum showed that those with the homozygous mutation had an altered AHSG protein size, whereas those who were heterozygous carriers of the mutation had only a single normal protein band. Reza Sailani et al. (2017) speculated that the R317H mutation would disrupt phosphorylation or glycosylation sites needed for proper protein function.
Associations Pending Confirmation
Lavebratt et al. (2005) genotyped 356 overweight or obese (see 601665) and 148 lean Swedish men for 4 SNPs in the AHSG gene and found that homozygosity for the AHSG*2 haplotype (see 138680.0001) conferred an increased risk for leanness (OR, 1.90; p = 0.027). Lavebratt et al. (2005) concluded that AHSG modulates body mass.
In 176 unrelated Japanese individuals, Osawa et al. (2005) found significant differences in AHSG protein levels between 3 major AHSG genotypes, with the lowest levels in AHSG*2 homozygotes. There was no association between AHSG levels and serum calcium values, but there was a significant negative correlation with free phosphate levels. Osawa et al. (2005) concluded that the AHSG polymorphism causes hereditary variation in serum AHSG and phosphate levels.
Lehtinen et al. (2007) investigated whether polymorphisms in AHSG contribute to the development of calcified atherosclerotic plaque in the coronary and carotid arteries and to carotid artery intima-media thickness. Four SNPs in AHSG were nominally associated with coronary artery calcified plaque in European Americans with diabetes mellitus type 2 (T2DM; 125853) (p less than 0.05). Two 3-SNP haplotypes in the exon 6-7 region were associated with coronary calcification in European Americans with T2DM (p less than 0.06). They concluded that sequence variants in the AHSG gene affect the extent of coronary calcification in T2DM-affected European Americans, consistent with the known biologic role of AHSG in vascular calcification.
For a discussion of a possible association between Caffey disease (see 114000) and variation in the AHSG gene, see 138680.0005.
Jahnen-Dechent et al. (1997) proposed that the fetuin family of serum proteins inhibits unwanted mineralization. To test this hypothesis in animals, they cloned the mouse fetuin gene and generated mice lacking fetuin. Expression studies demonstrated that mice homozygous for the gene deletion lacked fetuin protein and that mice heterozygous for the null mutation produced roughly half the amount of fetuin protein produced by wildtype mice. Fetuin-deficient mice were fertile and showed no gross anatomic abnormalities. However, the serum inhibition of apatite formation was compromised in these mice as well as in heterozygotes. In addition, some homozygous fetuin-deficient female ex-breeders developed ectopic microcalcifications in soft tissues. These results corroborate a role for fetuin in serum calcium homeostasis. The fact that generalized ectopic calcification did not occur in fetuin-deficient mice proved that additional inhibitors of phase separation exist in serum.
In Ahsg-null mice, Mathews et al. (2002) observed increased basal and insulin (INS; 176730)-stimulated phosphorylation of the insulin receptor (147670) and the downstream signaling molecules mitogen-activated protein kinase (see 176948) and Akt (see 164730) in liver and skeletal muscle. Glucose and insulin tolerance tests in Ahsg-null mice indicated significantly enhanced glucose clearance and insulin sensitivity. When fed a high-fat diet, Ahsg-null mice were resistant to weight gain, demonstrated significantly decreased body fat, and remained insulin sensitive. Mathews et al. (2002) suggested that AHSG may play a significant role in regulating postprandial glucose disposal, insulin sensitivity, weight gain, and fat accumulation.
This variant, formerly titled LEANNESS, SUSCEPTIBILITY TO, has been reclassified as a polymorphism.
Osawa et al. (1997) demonstrated that there is a double difference in the structure of the AHSG*1 and AHSG*2 alleles. AHSG*1 is characterized by ACG (thr) at position 230 in exon 6 and ACC (thr) at position 238 in exon 7 (138680.0002); AHSG*2 is characterized by ATG (met) at position 230 and AGC (ser) at position 238. Osawa et al. (2005) found association between the AHSG*2 haplotype and lower AHSG protein levels.
Lavebratt et al. (2005) genotyped 356 overweight or obese (see 601665) and 148 lean Swedish men for 1 intronic and 3 nonsynonymous SNPs in the AHSG gene and found that homozygosity for a haplotype comprising the rs2593813 G allele and the AHSG*2 allele (rs4917 met and rs4918 ser) conferred an increased risk for leanness (OR, 1.90; p = 0.027). The authors designated the polymorphism THR248MET based on a different numbering system. Lavebratt et al. (2005) suggested that a low level of AHSG is protective against fatness.
This variant, formerly titled LEANNESS, SUSCEPTIBILITY TO, has been reclassified as a polymorphism.
See 138680.0001 and Lavebratt et al. (2005).
Lavebratt et al. (2005) designated the polymorphism THR256SER based on a different numbering system.
This variant, formerly titled LEANNESS, SUSCEPTIBILITY TO, has been reclassified as a polymorphism.
See 138680.0001 and Lavebratt et al. (2005).
In 7 affected members of a large consanguineous Iranian family with alopecia-intellectual disability syndrome-1 (APMR1; 203650), Reza Sailani et al. (2017) identified a homozygous c.950G-A transition (c.950G-A, NM_001622) in exon 7 of the AHSG gene, resulting in an arg317-to-his (R317H) substitution at a highly conserved residue in the propeptide within a phosphorylation motif that is proteolytically processed posttranslationally to yield the mature protein. The mutation, which was found by whole-exome sequencing and confirmed by Sanger sequencing, segregated with the disorder in the family. The variant was filtered against several public databases and found at a very low frequency in the dbSNP (build 144) and ExAC databases, but not in homozygous state. The findings were also confirmed by linkage analysis in the family. The mutation was predicted to alter protein phosphorylation, and Western blot analysis and immunoprecipitation studies of serum showed that those with the homozygous mutation had an altered AHSG protein size, whereas those who were heterozygous carriers of the mutation had only a single normal protein band. Reza Sailani et al. (2017) speculated that the R317H mutation would disrupt phosphorylation or glycosylation sites needed for proper protein function.
This variant is classified as a variant of unknown significance because its contribution to Caffey disease (see 114000) has not been confirmed.
By whole-exome sequencing in a boy with Caffey disease, who was negative for the Caffey disease-associated c.3040C-T mutation in the COL1A1 gene (120150.0063), Merdler-Rabinowicz et al. (2019) identified homozygosity for a c.4A-T transversion in the AHSG gene, resulting in a lys2-to-ter (K2X) substitution. His unaffected first-cousin parents were heterozygous for the mutation, which was not found in the gnomAD database. No fetuin-A was detected in the proband's serum, whereas his heterozygous parents had levels similar to those of adult controls. The proband presented at age 9 weeks with right arm swelling that had developed gradually over several weeks. Examination revealed a firmly swollen right arm, hard in consistency, and x-rays showed exuberant periosteal reaction along the entire shaft of the right humerus. Skeletal survey showed significant periosteal reaction of the scapula, fibula, mandible, and multiple ribs. Laboratory evaluation showed a mild leukocytosis and elevated alkaline phosphatase, erythrocyte sedimentation rate, and C-reactive protein (123260). Treatment with the nonsteroidal antiinflammatory drug indomethacin resulted in reduction of the lesions within several months, and at 1 year of follow-up, the patient was completely well with no bone deformity or elevated inflammatory markers. He was maintained on low-dose indomethacin.
Anderson, L., Anderson, N. G. High resolution two-dimensional electrophoresis of human plasma proteins. Proc. Nat. Acad. Sci. 74: 5421-5425, 1977. [PubMed: 271964] [Full Text: https://doi.org/10.1073/pnas.74.12.5421]
Boutin, B., Feng, S. H., Arnaud, P. The genetic polymorphism of alpha(2)-HS glycoprotein: study by ultrathin-layer isoelectric focusing and immunoblot. Am. J. Hum. Genet. 37: 1098-1105, 1985. [PubMed: 4083279]
Cox, D. W., Andrews, B. J., Wills, D. E. Genetic polymorphism of alpha-2-HS-glycoprotein. Am. J. Hum. Genet. 38: 699-706, 1986. [PubMed: 3717159]
Cox, D. W., Andrews, B. J. Silver stain immunofixation for alpha-2-HS-glycoprotein: a new method for detection of protein heterogeneity. In: Stathakos, D. (ed.): Electrophoresis '82. Berlin: Walter de Gruyter (pub.) 1983. Pp. 243-247.
Cox, D. W., Francke, U., Allderdice, P. W., McAlpine, P. J. Gene mapping of human serum proteins using hepatoma hybrids and human chromosome deletions and duplications. Genetics 107 (suppl.): s22-s23, 1984.
Cox, D. W., Francke, U. Direct assignment of orosomucoid to human chromosome 9 and alpha-2-HS-glycoprotein to chromosome 3 using human fetal liver x rat hepatoma hybrids. Hum. Genet. 70: 109-115, 1985. [PubMed: 3859464] [Full Text: https://doi.org/10.1007/BF00273067]
Denecke, B., Graber, S., Schafer, C., Heiss, A., Woltje, M., Jahnen-Dechent, W. Tissue distribution and activity testing suggest a similar but not identical function of fetuin-B and fetuin-A. Biochem. J. 376: 135-145, 2003. [PubMed: 12943536] [Full Text: https://doi.org/10.1042/BJ20030676]
Eiberg, H., Mohr, J., Nielsen, L. S. A2HS: new methods of phenotyping and analysis of linkage relations: assignment to chromosome 3. (Abstract) Cytogenet. Cell Genet. 37: 461 only, 1984.
Gejyo, F., Chang, J.-L., Burgi, W., Schmid, K., Offner, G. D., Troxler, R. F., Van Halbeek, H., Dorland, L., Gerwig, G. J., Vliegenthart, J. F. G. Characterization of the B-chain of human plasma alpha(2)HS-glycoprotein: the complete amino acid sequence and primary structure of its heteroglycan. J. Biol. Chem. 258: 4966-4971, 1983. [PubMed: 6833285]
Jahnen-Dechent, W., Schinke, T., Trindl, A., Muller-Esterl, W., Sablitzky, F., Kaiser, S., Blessing, M. Cloning and targeted deletion of the mouse fetuin gene. J. Biol. Chem. 272: 31496-31503, 1997. [PubMed: 9395485] [Full Text: https://doi.org/10.1074/jbc.272.50.31496]
Jahnen-Dechent, W. Personal Communication. Meinz, Germany 7/22/1998.
Lavebratt, C., Wahlqvist, S., Nordfors, L., Hoffstedt, J., Arner, P. AHSG gene variant is associated with leanness among Swedish men. Hum. Genet. 117: 54-60, 2005. [PubMed: 15806395] [Full Text: https://doi.org/10.1007/s00439-005-1286-z]
Lee, C.-C., Bowman, B. H., Yang, F. Human alpha-2-HS-glycoprotein: the A and B chains with a connecting sequence are encoded by a single mRNA transcript. Proc. Nat. Acad. Sci. 84: 4403-4407, 1987. [PubMed: 3474608] [Full Text: https://doi.org/10.1073/pnas.84.13.4403]
Lehtinen, A. B., Burdon, K. P., Lewis, J. P., Langefeld, C. D., Ziegler, J. T., Rich, S. S., Register, T. C., Carr, J. J., Freedman, B. I., Bowden, D. W. Association of alpha-2-Heremans-Schmid glycoprotein polymorphisms with subclinical atherosclerosis. J. Clin. Endocr. Metab. 92: 345-352, 2007. [PubMed: 17062776] [Full Text: https://doi.org/10.1210/jc.2006-0429]
Magnuson, V. L., McCombs, J. L., Lee, C.-C., Yang, F., Bowman, B. H., McGill, J. R. Human alpha-2-HS-glycoprotein localized to 3q27-q29 by in situ hybridization. Cytogenet. Cell Genet. 47: 72-74, 1988. [PubMed: 3356172] [Full Text: https://doi.org/10.1159/000132509]
Mathews, S. T., Singh, G. P., Ranalletta, M., Cintron, V. J., Qiang, X., Goustin, A. S., Jen, K.-L. C., Charron, M. J., Jahnen-Dechent, W., Grunberger, G. Improved insulin sensitivity and resistance to weight gain in mice null for the Ahsg gene. Diabetes 51: 2450-2458, 2002. [PubMed: 12145157] [Full Text: https://doi.org/10.2337/diabetes.51.8.2450]
Merdler-Rabinowicz, R., Grinberg, A., Jacobson, J. M., Somekh, I., Klein, C., Lev, A., Ihsan, S., Habib, A., Somech, R., Simon, A. J. Fetuin-A deficiency is associated with infantile cortical hyperostosis (Caffey disease). Pediat. Res. 86: 603-607, 2019. [PubMed: 31288248] [Full Text: https://doi.org/10.1038/s41390-019-0499-0]
O'Farrell, P. H. High resolution two-dimensional electrophoresis of proteins. J. Biol. Chem. 250: 4007-4021, 1975. [PubMed: 236308]
Osawa, M., Tian, W., Horiuchi, H., Kaneko, M., Umetsu, K. Association of alpha-2-HS glycoprotein (AHSG, fetuin-A) polymorphism with AHSG and phosphate serum levels. Hum. Genet. 116: 146-151, 2005. [PubMed: 15592877] [Full Text: https://doi.org/10.1007/s00439-004-1222-7]
Osawa, M., Umetsu, K., Ohki, T., Nagasawa, T., Suzuki, T., Takeichi, S. Molecular evidence for human alpha2-HS glycoprotein (AHSG) polymorphism. Hum. Genet. 99: 18-21, 1997. [PubMed: 9003486] [Full Text: https://doi.org/10.1007/s004390050302]
Osawa, M., Umetsu, K., Sato, M., Ohki, T., Yukawa, N., Suzuki, T., Takeichi, S. Structure of the gene encoding human alpha 2-HS glycoprotein (AHSG). Gene 196: 121-125, 1997. [PubMed: 9322749] [Full Text: https://doi.org/10.1016/s0378-1119(97)00216-3]
Pedersen, K. O. Fetuin, a new globulin isolated from serum. (Letter) Nature 154: 575, 1944.
Reza Sailani, M.., Jahanbani, F., Nasiri, J., Behnam, M., Salehi, M., Sedghi, M., Hoseinzadeh, M., Takahashi, S., Zia, A., Gruber, J., Lynch, J. L., Lam, D., Winkelmann, J., Amirkiai, S., Pang, B., Rego, S., Mazroui, S., Bernstein, J. A., Snyder, M. P. Association of AHSG with alopecia and mental retardation (APMR) syndrome. Hum. Genet. 136: 287-296, 2017. [PubMed: 28054173] [Full Text: https://doi.org/10.1007/s00439-016-1756-5]
Rizzu, P., Baldini, A. Three members of the human cystatin gene superfamily, AHSG, HRG, and KNG, map within one megabase of genomic DNA at 3q27. Cytogenet. Cell Genet. 70: 26-28, 1995. [PubMed: 7736783] [Full Text: https://doi.org/10.1159/000133984]
Roychoudhury, A. K., Nei, M. Human Polymorphic Genes: World Distribution. New York: Oxford Univ. Press (pub.) 1988.
Srinivas, P. R., Wagner, A. S., Reddy, L. V., Deutsch, D. D., Leon, M. A., Goustin, A. S., Grunberger, G. Serum alpha(2)-HS-glycoprotein is an inhibitor of the human insulin receptor at the tyrosine kinase level. Molec. Endocr. 7: 1445-1455, 1993. [PubMed: 7906861] [Full Text: https://doi.org/10.1210/mend.7.11.7906861]
Terkelsen, O. B. F., Jahnen-Dechent, W., Nielsen, H., Moos, T., Fink, E., Nawratil, P., Muller-Esterl, W., Mollgard, K. Rat fetuin: distribution of protein and mRNA in embryonic and neonatal rat tissues. Anat. Embryol. (Berl.) 197: 125-133, 1998. [PubMed: 9497155] [Full Text: https://doi.org/10.1007/s004290050124]
Umetsu, K., Kashimura, S., Ikeda, N., Suzuki, T. A new alpha-2-HS-glycoprotein allele (AHS*5*) in two Japanese families. Hum. Genet. 68: 264-265, 1984. [PubMed: 6500579] [Full Text: https://doi.org/10.1007/BF00418399]
Umetsu, K., Kashimura, S., Ikeda, N., Suzuki, T. A new alpha-2-HS-glycoprotein typing by isoelectric focusing. Hum. Genet. 67: 70-71, 1984. [PubMed: 6745928] [Full Text: https://doi.org/10.1007/BF00270561]
Umetsu, K., Yuasa, I., Ikuta, M., Suzuki, T. Alpha-2-HS-glycoprotein (A2HS) polymorphism in a Japanese population: existence of two new variants. Jpn. J. Hum. Genet. 32: 263-266, 1987.
Umetsu, K., Yuasa, I., Nishimura, H., Sasaki, H., Suzuki, T. Genetic polymorphisms of orosomucoid and alpha-2-HS-glycoprotein in a Philippine population. Hum. Hered. 38: 287-290, 1988. [PubMed: 3235093] [Full Text: https://doi.org/10.1159/000153801]
Umetsu, K., Yuasa, I., Suzuki, T. The polymorphism of desialyzed alpha-2-HS-glycoprotein (AHS): isoelectric focusing in 2.5M urea as a method for identification of genetic variants. Hum. Genet. 73: 372-373, 1986. [PubMed: 3744364] [Full Text: https://doi.org/10.1007/BF00279104]
Yoshioka, Y., Gejyo, F., Marti, T., Rickli, E. E., Burgi, W., Offner, G. D., Troxler, R. F., Schmid, K. The complete amino acid sequence of the A-chain of human plasma alpha-2HS-glycoprotein. J. Biol. Chem. 261: 1665-1676, 1986. [PubMed: 3944104]
Zelinski, T., Kaita, H., Lewis, M., Coghlan, G., Craig, D. The sequence of chromosome 3 loci AHSG:TF:CHE1. Hum. Hered. 37: 1-6, 1987. [PubMed: 3557458] [Full Text: https://doi.org/10.1159/000153670]