Growth Hormone Receptor Gene Polymorphisms Research Articles

ASSOCIATION OF GROWTH HORMONE RECEPTOR (GHR) GENE POLYMORPHISMS WITH BODY WEIGHT OF RABBITS: A SYSTEMATIC REVIEW AND META-ANALYSIS

The growth hormone receptor (GHR) gene plays a key role in regulating growth and metabolism. However, the relationship between polymorphic variants of this gene and the body weight of rabbits under different genetic models has not been established. Thus, the objective of this study was to evaluate relationship between GHR gene polymorphisms and body weight of rabbits. Relevant literatures were systematically reviewed using the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guideline. 248 studies were identified and screened against pre-determined inclusion criteria and data were extracted from 17 studies. Each study was subjected to Hardy-Weinberg Equilibrium (HWE) test and six genetic models consisting of co-dominant, dominant, recessive and over-dominant models were fitted using OpenMeta® Analyst Software. The Cohen’s d method was used to calculate standardized mean differences (SMDs) to estimate individual study effect size as well as the overall effect size. Heterogeneity measures were inferred from the Q statistic (based on Chi-square test) and its associated p-value, Tau-squared (τ2), H-squared (H2) and I-squared (I2) values. Publication bias was assessed by Egger’s regression asymmetry test and sensitivity analysis was conducted to detect if the overall effect size was largely due to a single study effect size. There was significant association (P<0.05) of GHR gene with body weight of rabbits under one of the co-dominant models (CG vs GG). However, this association was not significant (P>0.05) under all other genetic models. Further, the results indicated that, cumulatively for all studies included in the meta-analysis of association of GHR gene with body weight of rabbits, GG genotype had higher body weight than CG genotype. However, there was no difference (P>0.05) between CC and CG and CC and GG genotypes. These findings implied that the impact of GHR gene polymorphisms on body weight in rabbits may be influenced by specific genetic models.

Prevalence of growth hormone receptor gene polymorphisms and their association with milk production and fertility-related traits of cross-bred dairy cows in Sri Lanka

This study investigated the association of selected growth hormone receptor (GHR) gene SNPs with selected fertility and milk production-related phenotypes of cross-bred dairy cows (n = 153) reared on three National Livestock Development Board farms in Sri Lanka. Selected cows were genetically screened for SNPs in the exon 08 (n = 153) and 5’ upstream (n = 118) regions of the GHR gene using the target sequencing method. The relationships between different genotypes and fertility traits (average calving interval, average number of services per conception, and age at first calving) and milk production-related traits (average total lactation yield, average lactation length, and average milk yield) were analyzed using the General Linear Model in SPSS. Among the identified Four GHR SNPs, rs1099014416 was significantly associated with average calving interval and age at first calving. Cows with GG genotype exhibited younger age at first calving (918.51 ± 113.42 days) and longer calving intervals (543.41 ± 43.29 days) compared to cows with GT (1275.18 ± 38.31, 515.09 ± 24.49 days) and TT (1212.89 ± 88.22, 364.52 ± 54.01 days) genotypes. Other SNPs did not show associations with the studied traits. SNP rs109014416 has the potential to be used as a genetic marker for fertility-related traits in the selection of cross-bred dairy cows in Sri Lanka which should be validated with a larger population.

Association Between Growth Hormone Receptor Gene Polymorphisms rs6180, rs6182, and rs6184 and Craniofacial Parameters in Indian Population

Objective/Background Craniofacial growth and development is influenced by growth hormone, which is in turn facilitated by the growth hormone receptor (GHR). GHR gene polymorphisms have been found to be associated with mandibular morphology and skeletal facial profiles in various populations. The aim of this study was to determine the association of single nucleotide polymorphisms (SNP) of GHR gene rs6180, rs6182, and rs6184 with maxillomandibular parameters in the Indian population. Setting and Sample Population A cross sectional study was conducted on 174 male and female Indian subjects in the age range of 20 to 32 years who reported for orthodontic treatment. Material and Methods Venous blood and lateral cephalogram were collected from each participant for genetic and cephalometric analysis. Genotypes of each SNP were identified by polymerase chain reaction—restriction fragment length polymorphism. Independent t test and Analysis of Variance (ANOVA) were done for intra and inter group comparisons with SPSS software. Results SNPs rs6180, and rs6182 were found to be associated with sagittal position and length of maxilla and mandible, anterior facial height, and growth pattern. SNP rs6184 did not have any significant association with the craniofacial parameters. Conclusion The results suggest that the GHR gene might be a candidate gene for maxillomandibular morphology in the Indian population.

62. Prevalence of growth hormone receptor gene polymorphisms and their possible impact on fertility traits and milk yield of cross-bred dairy cows in Sri Lanka

62. Prevalence of growth hormone receptor gene polymorphisms and their possible impact on fertility traits and milk yield of cross-bred dairy cows in Sri Lanka

Common Polymorphisms of Growth Hormone: Growth Hormone Receptor Axis in Turkish Children with Short Stature.

Objective: A single-nucleotide polymorphism of the growth hormone 1 gene, GH1IVS4+90A>T (rs2665802), associated with short stature and a polymorphism of the growth hormone receptor gene, exon 3 deleted variant, associated with increased responsiveness to growth hormone have been reported previously. We aimed to investigate the frequency of both polymorphisms and their correlation to height in Turkish short children. Also, we aimed to evaluate the effect of exon 3 deleted variant on response to 1-year growth hormone therapy.Materials and Methods: Children with idiopathic isolated growth hormone deficiency (n = 39) and with idiopathic short stature (n = 10) and 50 control subjects were evaluated for anthropometric parameters, annual growth velocity, and annual height gain. Growth hormone receptor gene polymorphisms were analyzed via multiplex polymerase chain reaction; growth hormone 1 gene polymorphism was analyzed via polymerase chain reaction and single-strand conformation polymorphism techniques.Results: The frequency of genotypes carrying the “A” allele was not significantly higher in the idiopathic isolated growth hormone deficiency group than in the idiopathic short stature and control groups (P = .03 for each). The exon 3 deleted variant genotype was significantly lower in the idiopathic short stature group compared to the control group (P = .01). There was no effect of exon 3 deleted variant, on response to the first-year growth hormone therapy.Conclusion: In Turkish population, no correlation was found between the “A” allele of GH1IVS4+90A>T polymorphism and idiopathic isolated growth hormone deficiency and short stature, and a significant negative correlation was found between exon 3 deleted variant and idiopathic short stature and short stature. Exon 3 deleted variant has no effect on response to growth hormone treatment.

Association of GHR|AluI gene polymorphism with body weight parameters in Grati-PO cattle

The growth hormone receptor (GHR) gene is member of the class I cytokine receptor family that important in growth regulation including in cattle. This study aimed to analyze the association between GHR|AluI gene with body weight, parameters in Grati-PO cattle population. A total of 304 blood samples were collected from the experimental station at the Beef Cattle Research Station, which were also equipped with 304 phenotypic data. DNA was extracted using a zymo extraction kit. Detection of of the polymorphism of GHR gene using PCR-RFLP method with AluI restriction enzymes. polymorphism indicators include genotype frequency, allele frequency, Hardy-Weinberg Equilibrium, observed heterozygosity (Ho), expected heterozygosity (He), polymorphism information content (PIC) and number of effective alleles (Ne). Association analysis was carried out using a linear mixed model. The performance of birth weight, weaning weight, yearling weight and 18 months weight were 25.4 + 0.2 kg; 113.8 + 2.3 kg; 159.9 + 2.7 kg and 213.7 + 3.6 kg, respectively. The result of association analysis was significant (P<0.05) on weaning weight, yearling weight and 18 months weight. It could be concluded that the GHR gene has potential to be a candidate genetic marker for growth traits in Grati-PO cattle.

Keragaman Gen Growth Hormone Receptor (GHR) Ekson 10 pada itik Sikumbang Janti

Growth Hormone Receptor (GHR) gene play important roles in duck performances due to their crucialfunctions in growth and has been considered as a candidate gene for growth traits. This reasearch wasaimed to indification polymorphism of Growth Hormon Receptor (GHR) gene in Sikumbang Janti duckand this study used 68 blood duck. Polymerase chain reaction (PCR) and sequencing analysis wereconducted to detect SNP existence in exon 10 of GHR gene. The result of this study showed that wasfound two SNP at g.1112 A>G and g.1304 C>T with transision mutation in exon 10 GHR gene. Genotypesfound in the g.1112 A>G were AA and GG with types of Allele A and G. Genotypes found in the g.1304T>C the were TT and CC with types of Allele T and C. Polymorphism of GHR gene were polymorphicand Population of Sikumbang Janti duck in Hardy-Weinberg equilibrium. It could be concluded thatGHR gene has potential to can be marker genetic in Sikumbang Janti ducks.

Association analysis of novel SNPs in exon 10 of the growth hormone receptor gene with growth traits in Indian sheep

The growth hormone receptor (GHR) gene encodes the type I cytokine receptor that helps in joining the growth hormone to this receptor, thus promoting receptor-dimerization, leading to up-regulating growth. The ovine GHR gene located on chromosome 16, which consists of 10 exons and 9 introns, along with untranslated regions on either side, comprise a total size of 178.09 kb. However, earlier reports about polymorphism have mainly dealt with exon 10 which is also a larger fragment of this gene comprising 1102 bp. Hence, this study was carried out to detect polymorphism in exon 10 of the GHR gene and its association with growth traits. Genomic DNA was isolated from blood samples of Madras Red and Mecheri sheep breeds from India. Part of exon 10 (895 bp) of the GHR gene was amplified and sent for sequencing. The sequence analysis revealed transition of nucleotide G>A at loci G177624A and G177878A in both sheep breeds. Populations were screened by Tetra-primer ARMS-PCR. The genotype frequencies of GG, GA and AA were 0.276, 0.519 and 0.205 at 177624 G>A, and 0.307, 0.444 and 0.149 at 177878 G>A in Madras Red sheep; whereas in Mecheri they were 0.476, 0.372 and 0.152 at 177624 G>A, and 0.629, 0.314 and 0.057 at 177878 G>A, respectively. Likewise the estimated allele frequencies of G and A were 0.5355 and 0.4645 at 177624 G>A, and 0.5790 and 0.4210 at 177878 G>A in Madras Red sheep; whereas in Mecheri they were 0.6620 and 0.3380 at 177624 G>A, and 0.7860 and 0.2140 at 177878 G>A, respectively. The effect of sex was significant for birth, six and nine month weight; but non-significant for three and 12 month weight in Mecheri sheep. However, in the Madras Red breed the effect of sex was significant for all body weights except weaning weight. The effect of variations on growth traits, viz., birth weight, weight at weaning, and weight at six, nine and twelve months in both breeds were analysed for their association, and they were found non-significant. Since these SNPs are salient findings of GHR gene polymorphism in Indian sheep breeds, further investigation is required into the significant effects of these novel SNPs, which could be useful for genetic improvement based on marker assisted selection.

Association between growth hormone receptor gene polymorphism and craniofacial morphology – A review

Craniofacial development is a sophisticated process which has multiple genetic and epigenetic factors involved. Disturbance in the developmental process can cause morphologic and functional defects, which may also affect the psychological health of the individual. It is imperative for orthodontists to have a thorough knowledge about the growth of the face in general and of the maxilla and mandible in particular, to help modify growth and treat the skeletal malocclusions. Multiple genes have been implicated in the growth of the craniofacial complex, growth hormone receptor gene (GHR) being one of them. Growth hormone plays an important role in the post-natal development of an organism, both skeletal and soft tissue growth. Mutation of its receptor will affect the expression of the gene, and in turn influence the growth. Studies have shown that polymorphisms in the GHR gene receptors affect the morphology of the maxillomandibular skeleton. This article is a review about the polymorphisms of the GHR gene which affect the facial skeletal pattern.

PROFIL GEN RECEPTOR GROWTH HORMONE (rGH) PADA SAPI MADRASIN

Cross-breeding between Madura cattle and exotic breeds (exotic cows) occurs in Madura area. The reality in the field shows that the cross-breeding occurs between Limousin cow and Madura cow and the result of the breeding is called as Madrasin cow. One of factor that influences the animal’s growth is Growth Hormone Receptor (GHR). GHR is needed by Growth Hormone (GH) to carry out its effects on target tissues. The purpose of this study is to identify the profile of Growth Hormone Receptors in Madrasin cow. This research was conducted on farmers in Bangkalan, East Java and the Center of Veterinary, Denpasar in MayJune 2017. This study used 14 cows Madrasin. The samples of this study were blood which were taken and used for analyzing DNA that includes DNA isolation, DNA amplification by using Polymerase Chain Reaction (PCR) and Restriction Fragment Length Polymorphism (RFLP) method to determine the genotype. An identification of Growth Hormone Receptor gene polymorphism is done through digesting the DNA fragment of 298 bp by the restriction enzyme AluI. The results shows that the frequency of Growth Hormone Receptor Gene of cow Madrasin allele A was 0.92 and the G allele was 0.08 with frequency of the A allele is higher than G allele.The genotype changing was found in cow Madrasin as much as 0.85 to 0.14 for the AA and AG. As a result of the study, the researcher concluded that Growth Hormone Receptor gene experienced a changing or polymorphisms in Madrasin cow and information which stated in this study be able to used as a basic for selection.

Association Between Growth Hormone Receptor Gene Polymorphism and Body Weight in Growing Rabbits

Association Between Growth Hormone Receptor Gene Polymorphism and Body Weight in Growing Rabbits

English

English

Growth hormone receptor (GHR) gene polymorphism and scoliosis in Prader-Willi syndrome

ObjectiveA growth hormone receptor (GHR) gene polymorphism impacts sensitivity to endogenous and exogenous growth hormone (GH) to moderate growth and development. Increased sensitivity may accelerate spinal growth and contribute to scoliosis, particularly in GH-deficient and treated populations such as Prader-Willi syndrome (PWS). Therefore, we examined the relationship between GHR genotype and scoliosis (case and control) in PWS cohorts. DesignWe utilized a case-control design in a study of 73 subjects (34M; 39F) with genetically confirmed PWS in 32 individuals previously diagnosed with moderate to severe scoliosis (mean age=16.9±10.2years; age range of 1 to 41years) and 41 adults with no evidence of scoliosis (mean age=30.8±9.7years; age range of 18 to 56years). The GHR gene polymorphism was determined using PCR specific primers to capture the two recognized GHR gene fragment sizes [i.e., full length (fl) or exon 3 deletions (d3)]. ResultsTwenty-three (72%) of the 32 case subjects with scoliosis required surgical correction with an approximately equal balance for gender and PWS genetic subtype among cases and 41 control subjects without scoliosis. The GHR d3/d3 genotype was identified in N=2 of 8 (25%) cases with scoliosis and the d3/fl genotype was identified in N=11 of 25 (44%) cases with scoliosis but the distribution difference did not statistically differ. The GHR fl/fl genotype was correlated with a significantly faster rate and heavier weight gain among case subjects. ConclusionOur examination of demographic and genetic markers associated with scoliosis and surgical repair in PWS found no evidence to support differences in gender, PWS genetic subtype or GHR d3 allele distributions among the case vs control groups. Those with fl/fl alleles were heavier than those with d3/d3 or d3/fl genotypes and warrant further study with a larger sample size and possibly to include other vulnerable populations requiring growth hormone treatment.

Polymorphism of growth hormone receptor (GHR) gene in Pasundan cattle

Putra WPB, Agung PP, Anwar S, Said S, Hermansyah A. 2017. Polymorphism of growth hormone receptor (GHR) gene in Pasundan cattle. Pros Sem Nas Masy Biodiv Indon 3: 299-303. Identification of genetic polymorphism which controlling to the growth traits could be used as molecular selection for livestock. The objective of this study was to identify the genetic polymorphism of GHR in Pasundan cattle. Total of 119 DNA samples of Pasundan cattle that kept at BSD-BC of Ciamis, West Java was used in this study. The method used in the present study was PCR-RFLP with AluI (AG*CT) restriction enzyme. The result of this study showed that the GHR gene (298 bp) of Pasundan cattle were polymorphic with three genotype type of AA (0.412); AG (0.429) and GG (0.160). The Allelic frequencies of A and G were 0.626 and 0.374 respectively. The estimation of allelic effective numbers (Ne) was 1.873 and no fixation effect indicated (Fis<1.00). The Chi-square (χ2) test showed that the genotypic frequencies of GHR gene in the population tested was in the Hardy-Weinberg equilibrium (HWE). The observed of heterozygosity (Ho) values in this study were higher than expected of heterozygosity (He) value. The polymorphism information content (PIC) value was 0.358 (moderate). The conclusion of this study conducted that the GHR gene of Pasundan cattle was polymorphic and might be used as molecular selection through intensive study. Additional sample from another Pasundan’s population places are needed to provide accurate information about the polymorphism of GHR gene in Pasundan cattle.

The exon3-deleted growth hormone receptor gene polymorphism (d3-GHR) is associated with insulin and spontaneous growth in short SGA children (NESGAS)

ObjectiveThe effect of a common polymorphism in the Growth Hormone (GH) receptor (d3-GHR) gene on growth, metabolism and body composition was examined in short children born small for gestational age (SGA) on GH treatment. DesignIn 96 prepubertal, short SGA children treated with high-dose GH (67μg/kg/day) in the NESGAS study, insulin sensitivity (IS), insulin secretion and disposition index (DI) were determined during the first year of treatment. Body composition was analysed by DXA. The d3-GHR locus was determined by simple multiplex PCR. ResultsAt baseline, children in the d3-GHR group (d3/fl (n=37), d3/d3 (n=7)) had significantly lower IS (median (25–75 percentile)) (223.3% (154.4–304.8)) vs. (269.7% (185.1–356.7)) (p=0.03) and higher concentrations of glucose (mean (SD)) (4.4mmol/L (0.6) vs. 4.2mmol/L (0.7)) (p=0.03), C-peptide (232.1pmol/L (168.8–304.1) vs. 185.1pmol/L (137.7–253.9)) (p=0.04) and insulin (19.2pmol/L (11.8–32.2)) vs. (13.7pmol/L (9.3–20.8)) (p=0.04) compared to children homozygous for the full length allele (fl/fl-GHR (n=52)). There were no differences in DI or insulin secretion. Postnatal, spontaneous growth was significantly greater in the d3-GHR group compared to the fl/fl-GHR group (p=0.02). There were no significant differences in growth response, body composition or metabolism after one year of GH therapy. ConclusionShort SGA children carrying the d3-GHR polymorphism had increased spontaneous growth, lower IS and a compensatory increase in glucose, C-peptide and insulin before GH therapy compared to children homozygous for the full-length allele.

Association study between growth hormone receptor (GHR ) gene polymorphisms and obesity in Korean population.

A main target of growth hormone (GH) is adipose tissue in human body. The GH secretion in obesity patients is impaired. It is needless to say that growth hormone receptor (GHR) is necessary in GH hormone signaling. The purpose of the present study is to examine the association between single nucleotide polymorphisms (SNPs) and the development of obesity. A total of 211 overweight/obese subjects with a body mass index (BMI) ≥23 kg/m2 and 157 nonoverweight/obese controls with a BMI of 18.5–23.0 kg/m2 were involved in this study. Seven SNPs including the rs6451620 (intron), rs4130114 (intron), rs4410646 (intron), rs6898743 (intron), rs4394131 (intron), rs6182 (Cys440Phe), and rs6184 (Pro579Thr) and rs2229765 SNPs of GHR gene were genotyped. Genotyping was performed using custom DNA chip. SNPStats was used to calculate the odds ratio, 95% confidence interval, and P-value. The link-age disequilibrium block and haplotypes among seven SNPs were determined using Haploview version 4.2. Dominant, recessive, and log-additive genetic models were conducted for genetic analyzing. Among tested SNPs in GHR gene, rs4410646 and rs6898743 showed significant association with obesity (rs4410646, P=0.02 in dominant model and P=0.036 in log-additive model; rs6898743, P=0.039 in dominant model and P=0.044 in log-additive model). In summary, these results suggest that GHR gene polymorphisms might play a role in the development of obesity in the Korean population.

A determination of growth hormone receptor gene polymorphisms in East Anatolian Red cattle, South Anatolian Red cattle, and Turkish Grey cattle

The objective of this study was to determinate the genotype and allele distributions of growth hormone receptor gene polymorphisms in East Anatolian Red cattle (EAR), South Anatolian Red cattle (SAR), and Turkish Grey (TG) cattle. To this end, 50 EAR, 50 SAR, and 50 TG cattle were used in the study. DNA samples were isolated by using the standard ammonium acetate salt-out method. Target regions were amplified and digested by AluI, AccI, StuI, NsiI, and Fnu4HI restriction enzymes. The + allele frequency of growth hormone receptor (GHR)/AluI polymorphism related with milk traits in TG cattle and the - allele frequencies of GHR/AluI polymorphism related with meat traits in EAR and SAR cattle were found to be low. The + allele frequency of GHR/StuI polymorphism affecting milk traits was found to be low in the EAR breed. The -/- genotype of GHR/NsiI polymorphism was also low in all 3 of the breeds. The + allele frequency of GHR/Fnu4HI polymorphism related with meat traits turned out to be low in the SAR and EAR breeds. In conclusion, it can be said that some of the alleles of GHR polymorphisms that are favorable for trait qualities occur less frequently in SAR, EAR, and TG cattle breeds than they do in high-trait European breeds.

Association of the growth hormone receptor gene polymorphisms with mandibular height in a Korean population

Growth hormone receptor gene ( GHR) is one of the likely candidates for determining morphological traits, because GH is a key regulator of bone growth. The genetic association of GHR in exon 10 with mandibular ramus height has been found in different populations, Japanese and Chinese. On the other hand, two common isoforms of GHR, one full-length ( fl-GHR) and the other lacking the extracellular domain encoded by exon 3 ( d3-GHR), are associated with differences in responsiveness to GH. The purpose of this study involving 159 Korean subjects was to study the associations between a GHR polymorphism ( d3/fl- GHR) that results in genomic deletion of exon 3 and craniofacial morphology, and to study the associations between GHR genotypes in exon 10 and craniofacial morphology. Moreover, the allelic frequencies in a multi-ethnic population (24 Han Chinese, 24 African-Americans, 24 European-Americans, and 24 Hispanics) in a GHR polymorphism ( d3/fl- GHR) were compared in this study. The five craniofacial linear measurements (cranial base length, maxillary length, overall mandibular length, mandibular corpus length, and mandibular ramus height) obtained from lateral cephalograms were examined as craniofacial morphology. We found that the d3/fl- GHR polymorphism had no association for any measurements, and a statistically significant association ( P = 0.024) between the GHR polymorphisms P561T and C422F in exon 10 and mandibular ramus height. Neither SNPs besides P561T and C422F polymorphisms in exon 10 nor the measurements besides mandibular ramus height have statistically significances. Both derived alleles at P561T and C422F SNPs were highly associated with only one haplotype, haplotype-4 in Korean population. As quantitative haplotype association, the results showed a significant difference in mandibular ramus height between individuals having one haplotype-4 and others without haplotype-4 ( P = 0.028). Moreover, we found that the d3/fl- GHR polymorphism showed diverse frequency in different population. Regarding GHR genotypes in exon 10, the present study mostly reflected the results obtained for a Japanese population, although our current study does not replicate the correlation between the I526L polymorphism of GHR and mandibular ramus height as was reported in a previous study of Han Chinese. The results of the present study suggest that the GHR exon 10 SNPs, not d3/fl- GHR, contribute to changes in the mandibular ramus height of Koreans.

Analysis of the correlations between growth hormone receptor gene polymorphism and body size indexes in cattle

Polymorphism in exon 10 of growth hormone receptor (GHR) was detected in three cattle breeds (Nanyang cattle, limousin and galloway), They were at A/T at nt. 495, C/T at nt. 622, A/C at nt. 650, T/C at nt. 702 and A/G at nt. 730. Results indicated that there were six genotypes, namely AA, BB, CC, AB, AC and BC. The frequencies of different genotypes in different breeds and the relationship between the six genotypes and traits of these cattle were analyzed using a linear model. Statistical results showed that the GHR SSCP sites in Nanyang, Limousin and Galloway cattle were at Hardy-Weinberg Equilibrium. The polymorphism information content (PIC) values indicated that the SSCPs were highly polymorphic (PIC < 0.50) in the Nanyang breed, and were moderately polymorphic in Limousin and Galloway breeds. The least squares means of body weight of 12-month-old cattle was lower for genotype CC than for genotypes AB and BC (P<0.05, P<0.01, respectively). The least squares means of body weight of 18-month-old cattle was lower for genotype CC than for BC (P < 0.05). The least squares means of heart girth in 18-month-old cattle was lower for genotype CC than for AB (P < 0.05). There was no difference in the genotype distribution among other genotypes.

Effects of GHR gene polymorphisms on growth and carcass traits in Zebu and crossbred beef cattle

The growth hormone receptor (GHR) is the cell surface receptor for growth hormone (GH) and is required for GH to carry out its effects on target tissues. The objectives of the present study were to estimate the allele and genotype frequencies of the GHR/Alu I gene polymorphism located in the regulatory region in beef cattle belonging to different genetic groups and to determine associations between this polymorphism and growth and carcass traits. Genotyping was performed on 384 animals, including 79 Nellore (Zebu), 30 Canchim (5/8 Charolais + 3/8 Zebu), 30 Simmental × Nellore crossbred and 245 Angus × Nellore crossbred cattle. Alleles Alu I(+), Alu I(−) and Alu I(N) –null allele–were evidenced for the GHR/ Alu I polymorphism and the frequency of the Alu I(N) allele was significantly higher than the frequency of the Alu I(+) and Alu I(−) alleles in all genetic groups. Genotype Alu I(N/N) of the GHR/ Alu I predominated in Nellore animals, while the Alu I(N/+) and Alu I(N/−) predominated in the other genetic groups. In the association studies, traits of interest were analyzed using the General Linear Model (GLM) procedure of the SAS program and least squares means of the genotypes were compared by the Tukey test. Significant associations ( P < 0.05) were observed between the Alu I(N/N) genotype of the GHR/ Alu I polymorphism and lower weight gain and body weight at slaughter, although a confounding between genotypes and genetic groups may have occurred.