Updated upper limits of normal serum alanine aminotrasferase levels for screening metabolic dysfunction-associated fatty liver disease in obese children.

BACKGROUND/PURPOSE: Alanine aminotransferase (ALT) is a cost-effective screening test for asymptomatic liver diseases. The aims of this study are to redefine the ULNs of ALT using the 2010-2012 Nutrition and Health Survey in Taiwan (NAHSIT) database and to determine whether the updated ULNs can better screen for metabolic dysfunction-associated fatty liver disease (MAFLD) in obese children. METHODS: Reference data were obtained from 2895 NAHSIT participants (1442 boys, 1453 girls) aged 6-18 years. Participants with any of MAFLD-related metabolic risk factors, including overweight/obesity, elevated triglyceride, low high-density lipoprotein cholesterol and high fasting glucose, were excluded. This study compared the sensitivities of different ULNs of ALT for detecting MAFLD in our previously established cohort of obese children. RESULTS: The ULNs of ALT defined as the 95th percentile in metabolically healthy NAHSIT participants were 23 IU/L for boys and 18 IU/L for girls. When using the updated ULNs, the percentages of elevated ALT levels were 13.0% in boys and 7.8% in girls of all NAHSIT participants. When using the updated ULNs of ALT to detect MAFLD in obese children, the sensitivity was 84.0% in boys and 74.3% in girls. In contrast, when using the conventional ALT cutoff (>40 IU/L), the sensitivity decreased to 61.4% in boys and 36.4% in girls. CONCLUSION: After taking into account MAFLD-related metabolic risk factors, the ULNs of ALT are 23 IU/L for boys and 18 IU/L for girls in Taiwan. The updated ULNs may be better cutoffs for screening MAFLD in obese children.

Predictors for incidence and remission of nonalcoholic fatty liver disease in obese children and adolescents.

BACKGROUND/PURPOSE: The status of nonalcoholic fatty liver disease (NAFLD) can wax and wane over time in children. However, the factors affecting its incidence and remission remain elusive. We aimed to investigate NAFLD incidence, remission and predicting factors in obese children. METHODS: Obese children aged 9-10 and 12-13 years were recruited from schools and followed up for 2 years. Liver ultrasonography was performed at baseline and Year 1. Alanine aminotransferase (ALT) concentrations were measured at baseline, Year 1 and Year 2. Elevated ALT was defined as above 26 U/L for boys and 22 U/L for girls. Four NAFLD susceptible genes, including PNPLA3, GCKR, TM6SF2 and MBOAT7, were genotyped. We analyzed the effects of these risk factors on the incidence and remission of NAFLD and elevated ALT. RESULTS: At baseline, 86 of 440 (19.5%) subjects had ultrasonography-diagnosed NAFLD. At Year 1, of 264 subjects without NAFLD at baseline, 20 (7.6%) developed NAFLD. The baseline BMI z-score and increment in BMI z-score independently predicted incident NAFLD. Of the 68 subjects with NAFLD at baseline, 36 (52.9%) had NAFLD remission. Decrement in BMI z-score independently predicted NAFLD remission. The four studied NAFLD susceptible genes were not significantly associated with either the incidence or remission of NAFLD. In addition, changes in BMI z-score predicted the incidence and remission of elevated ALT from Year 1 to Year 2. CONCLUSION: Obese children with increasing BMI are more likely to develop NAFLD and those with decreasing BMI are more likely to have NAFLD remission.

Genetic determinants of hepatic steatosis and serum cytokeratin-18 fragment levels in Taiwanese children.

BACKGROUND/AIMS: There are substantial genetic components contributing to the susceptibility of nonalcoholic fatty liver disease (NAFLD). It has recently been reported that the rs641738 C>T variant in the membrane-bound O-acyltransferase domain-containing protein 7 (MBOAT7) gene increased severity of NAFLD in adults of European descent. We aimed to test the hypothesis that MBOAT7 rs641738 variant would increase hepatic steatosis and hepatocellular injury in obese children. METHODS: A total of 831 obese children aged 7-15 years were recruited. Hepatic steatosis was measured by ultrasonography. Because PNPLA3 rs738409, GCKR rs780094 and TM6SF2 rs58542926 variants are known to confer susceptibility to NAFLD, we assessed the influence of MBOAT7 rs641738 on hepatic steatosis, and serum levels of CK-18 fragment (a biomarker of hepatocellular injury and apoptosis for NAFLD) after adjusting the effects of PNPLA3, GCKR and TM6SF2 polymorphisms. RESULTS: Of the recruited obese children, 22.7% had hepatic steatosis. PNPLA3 rs738409, GCKR rs780094 and TM6SF2 rs58542926 variants were independent risk factors of hepatic steatosis and elevated ALT levels. In contrast, MBOAT7 rs641738 variants, neither heterozygous nor homozygous genotypes, were not associated with hepatic steatosis, insulin resistance, lipid levels and liver enzymes. The multiple linear regression model revealed that after adjusting for age, gender, body mass index z score, PNPLA3 rs738409 and GCKR rs780094 variants, but not MBOAT7 rs641738, were associated with serum levels of CK-18 fragment. CONCLUSIONS: The variant MBOAT7 rs641738 genotype is not associated with hepatic steatosis and serum levels of CK-18 fragment in obese Taiwanese children.

Variants in the autophagy-related gene IRGM confer susceptibility to non-alcoholic fatty liver disease by modulating lipophagy.

BACKGROUND & AIMS: Autophagy has been shown to be crucial in the regulation of the intracellular lipid stores in hepatocytes. We hypothesize that immunity-related GTPase family M (IRGM) gene (an autophagy-related gene) variants confer the susceptibility to non-alcoholic fatty liver disease (NAFLD) development. METHODS: 832 obese children and adolescents aged 6-18years were recruited. NAFLD was determined by liver ultrasonography. We genotyped PNPLA3 rs738409, GCKR rs780094, TM6SF2 rs58542926, six IRGM single nucleotide polymorphisms (rs13361189, rs9637876, rs72553867, rs10065172, rs1000113, and rs11747270). To understand the molecular mechanism, we examined the effects of IRGM knockdown and overexpression on autophagic flux and lipid droplet metabolism in human hepatoma cells. RESULTS: 22.8% of recruited obese children and adolescents had NAFLD. Multiple logistic regression analysis revealed that after controlling for the effects of age- and gender-adjusted body mass index, gender, PNPLA3, GCKR, and TM6SF2 polymorphisms, variant IRGM rs10065172 TT genotype independently increased the odds ratio of NAFLD by 2.04 (95% confidence interval 1.22-3.42; p=0.007), as compared to the CC genotype. The predictive model was validated by means of 10-fold cross validation. Functional assay revealed that IRGM knockdown inhibited autophagic flux and increased lipid droplet content in HepG2 and PLC/PRF/5 cells, which were reversed by the autophagy inducer rapamycin administration. Similarly, wortmannin (an autophagy inhibitor) increased intracellular lipid droplet content. In contrast, overexpression of IRGM caused decreased lipid droplet content in HepG2 cells. CONCLUSIONS: Our findings suggest that IRGM may contribute to the development of human NAFLD by altering hepatic lipid metabolism through the autophagy pathway. LAY SUMMARY: Autophagy is involved in the process of lipid metabolism in hepatocytes. The mechanism of autophagy regulation by IRGM has just been unveiled. This study demonstrates that genetic variants in IRGM confer risk of human non-alcoholic fatty liver disease. The functional studies reveal how IRGM regulates hepatic lipid droplet content.

Differences of microbiota in small bowel and faeces between irritable bowel syndrome patients and healthy subjects.

OBJECTIVE: Several studies suggested that colonic microbiota have impacts on irritable bowel syndrome (IBS) patients. However, the knowledge about the association of small intestine (SI) microbiota with IBS is limited. We aimed to investigate the gut microbiota composition of SI and stool in IBS patients. MATERIALS AND METHODS: Biopsies of jejunum mucosa by balloon-assisted enteroscopy and faecal samples from 28 IBS patients and 19 healthy controls were analysed by next-generation sequencing method. RESULTS: The three major phyla in SI microbiota of case/control groups were Proteobacteria (32.8/47.7%), Bacteroidetes (25.2/15.3%), and Firmicutes (19.8/11.2%), and those of stool were Bacteroidetes (41.3/45.8%), Firmicutes (40.7/38.2%), and Proteobacteria (15.4/7.1%). Analysis based on the family level, IBS patients had a higher proportion of Veillonellaceae (mean proportion 6.49% versus 2.68%, p = 0.046) in stool than controls. Prevotellaceae was more abundant in IBS patients than in control group (14.27% versus 6.13%, p = 0.023), while Mycobacteriaceae (0.06% versus 0.17%, p = 0.024) and Neisseriaceae (6.40% versus 8.94%, p = 0.038) was less abundant in IBS patients' jejunal mucosa than those in controls. This less abundant jejunal Neisseriaceae was associated with more severe IBS (p = 0.03). The ratio of Firmicutes to Bacteroidetes in the stool of IBS-diarrhoea type patients was approximately three-fold higher, and the ratio of Firmicutes to Actinobacter in SI of IBS-mixed type patients was about nine-fold higher than healthy subjects. CONCLUSION: Higher abundance of colonic Veillonellaceae and SI Prevotellaceae, and lower amount of oral cavity normal flora in proximal SI were found in IBS patients. We may manipulate these bacteria in IBS patients in future studies (ClinicalTrial.gov Number NCT01679730).

Molecular biology of glucose-6-phosphate dehydrogenase and UDP-glucuronosyltransferase 1A1 in the development of neonatal unconjugated hyperbilirubinemia.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency and variants of the UDP-glucuronosyltransferase 1A1 (UGT1A1) gene are the most common genetic causes of neonatal unconjugated hyperbilirubinemia (NUH). In this review, we searched PubMed for articles on the genetic causes of NUH published before December 31, 2022, and analyzed the data. On the basis of the results, we reached eight conclusions: (1) 37 mutations of the G6PD gene are associated with NUH; (2) the clinical manifestation of G6PD deficiency depends not only on ethnicity but also on the molecular mechanisms underlying the deficiency (and thus its severity); (3) of mutations in the UGT1A1 gene, homozygous c.-53A(TA)6TAA > A(TA)7TAA is the main cause of NUH in Caucasians and Africans, whereas homozygous c.211G > A is the main genetic cause of NUH in East Asians; (4) in Indonesian neonates, homozygous c.-3279T > G is the most common cause of NUH development, and neither c.-53 A(TA)6TAA > A(TA)7TAA nor c.211G > A causes it; (5) in breast-fed East Asian neonates, the TA7 repeat variant of the UGT1A1 gene protects against the development of NUH; (6) G6PD deficiency combined with homozygous c.211G > A variation of the UGT1A1 gene increases the risk of severe NUH; (7) in Pakistani and Caucasian patients with Crigler-Najjar syndrome type 2 (CN-2), point mutations of the UGT1A1 gene are widely distributed and frequently occur with variation at nucleotide -53, whereas in Asian patients with CN-2, compound homozygous variations in the coding region are frequently observed; and (8) records of G6PD deficiency and UGT1A1 variation status for a neonate offer useful pharmacogenomic information that can aid long-term care. These results indicate that timely diagnosis of NUH through molecular tests is crucial and that early initiation of treatment for the neonates and educational programs for their parents improves outcomes.

Identifying term breast-fed infants at risk of significant hyperbilirubinemia.

BACKGROUND: The aim of this study was to establish a model to identify term breast-fed infants who are at risk of developing significant neonatal hyperbilirubinemia. METHODS: A prospective study was designed to investigate the effects of birth weight, mode of delivery, cephalohematoma, glucose-6-phosphate dehydrogenase (G6PD) deficiency, predischarge total serum bilirubin, variant uridine 5'diphospho-glucuronosyltransferase 1A1 (UGT1A1) gene, and hepatic solute carrier organic anion transporter 1B1 (SLCO1B1) gene on significant hyperbilirubinemia in term breast-fed neonates. Significant hyperbilirubinemia was defined as a bilirubin level exceeding the hour-specific phototherapy treatment threshold recommended by the American Academy of Pediatrics in 2004. RESULTS: Of 240 exclusively breast-fed term neonates, 26 (10.8%) had significant hyperbilirubinemia. The predischarge total serum bilirubin on the third day (odds ratio (OR) = 2.63; 95% confidence interval (CI): 1.87-3.70; P < 0.001) and the variant UGT1A1 gene at nucleotide 211 (OR = 5.00; 95% CI: 1.08-23.03; P < 0.05) were significant risk factors. The area under the receiver operating characteristic (ROC) curve of the predictive probability was 0.964 (95% CI: 0.932-0.984; P < 0.0001). CONCLUSION: Combining the total serum bilirubin on the third day and the variant UGT1A1 gene at nucleotide 211 can predict hyperbilirubinemia well in term breast-fed infants.

Risk of hyperbilirubinemia in breast-fed infants.

OBJECTIVE: To investigate the risk factors for hyperbilirubinemia in infants who are exclusively breast-fed. STUDY DESIGN: A prospective study was conducted to investigate the effects of birth body weight, sex, mode of delivery, glucose-6-phosphate dehydrogenase (G6PD) deficiency, variant UDP-glucuronosyltransferase 1A1 (UGT1A1) gene, and hepatic solute carrier organic anion transporter 1B1 (SLCO1B1) gene on hyperbilirubinemia in neonates who were breast-fed. Hyperbilirubinemia was diagnosed when a full term neonate had a bilirubin level ≧15.0 mg/dL (256.5 µM) in serum at 3 days old. The polymerase chain reaction-restriction fragment length polymorphism method was used as a means of detecting the known variant sites in the UGT1A1 and SLCO1B1 gene. RESULTS: Of 252 infants born at term who were exclusively breast-fed, 59 (23.4%) had hyperbilirubinemia. The significant risk factors were a variant nucleotide 211 in UGT1A1 (2.48; 95% CI, 1.29 to 4.76; P = .006), G6PD deficiency (12.24; 95% CI, 1.08 to 138.62; P < .05), and vaginal delivery (3.55; 95% CI, 1.64 to 7.66; P < .001). CONCLUSION: Breast-fed neonates who are 211 variants in the UGT1A1, G6PD deficiency, and vaginal delivery are at high-risk for hyperbilirubinemia.

A common variant in the PNPLA3 gene is a risk factor for non-alcoholic fatty liver disease in obese Taiwanese children.

OBJECTIVE: To test the hypothesis that the presence of the PNPLA3 rs738409 G allele would increase the susceptibility of non-alcoholic fatty liver disease (NAFLD) in obese Taiwanese children. STUDY DESIGN: A total of 520 obese children aged 6-18 years were recruited. Their PNPLA3 rs738409 genotypes-CC, CG, or GG-were detected by the 5'-nuclease assay. The effects of the PNPLA3 rs738409 G allele on pediatric NAFLD were evaluated based on liver ultrasonography findings and mean serum alanine aminotransferase levels in these children. RESULTS: NAFLD was present in 19.6% of the obese children. In comparison to the subjects with CC alleles, the risk of NAFLD was increased by 2.96-fold (95% CI, 1.57 to 5.59, P = .0008) in the subjects with CG alleles and by 5.84-fold (95% CI, 2.59 to 13.16; P < .0001) in those with GG alleles. Variant PNPLA3 rs738409 genotypes were associated with increases in mean serum alanine aminotransferase level of 4.77 IU/L (P = .0435) in subjects with CG alleles and of 10.86 IU/L (P < .0001) in those with GG alleles compared with subjects with CC alleles. CONCLUSIONS: The variant PNPLA3 rs738409 genotypes increased the risk of NAFLD in our population of obese Taiwanese children. The effect of the G allele on pediatric NAFLD followed a dominant genetic model.

Effects of variation status and enzyme activity for UDP-glucuronosyltransferase 1A1 gene on neonatal hyperbilirubinemia.

BACKGROUND: We found that Taiwanese adults carrying genotypes of UDP-glucuronosyltransferase (UGT) 1A1 with enzyme activity ≤40% of normal were at high risk for developing Gilbert's syndrome. However, the relationship between UGT1A1 activity and neonatal hyperbilirubinemia has never been evaluated for Taiwanese. METHODS: We enrolled 141 hyperbilirubinemic neonates partially fed supplementary infant formula and 432 controls; and 112 hyperbilirubinemic neonates exclusively breastfed and 493 controls. The five single nucleotide polymorphisms (SNPs) at nucleotides -53, 211, 686, 1091 and 1456 in the UGT1A1 gene were determined and UGT1A1 activity was estimated. Odds ratios (ORs) of variation status in the UGT1A1 gene and enzyme activity for the development of neonatal hyperbilirubinemia were calculated, respectively. RESULTS: For neonates partially fed supplementary infant formula, the adjusted OR (AOR) for the development of hyperbilirubinemia was significantly higher in the neonates carrying the homozygous variation (211AA) in the UGT1A1 gene than for those carrying the wild type (AOR = 6.00, p < 0.001). Only the AOR of those carrying UGT1A1 activity ranked 31-40% of normal was statistically significant (AOR = 3.16, p < 0.001). For the hyperbilirubinemic neonates exclusively breastfed, AOR for the development of hyperbilirubinemia is positively correlated to degree of variation (AOR = 1.95, 2.19 and 4.53; with p = 0.003, 0.05 and < 0.001, respectively), while the effect of UGT1A1 enzyme activity was varied (AOR = 1.02-3.72, with p = 0.95∼<0.001). CONCLUSION: The estimated enzyme activity depending on combination of SNPs (genotypes) in the UGT1A1 gene could not be utilized to explain the development of neonatal hyperbilirubinemia. We reconfirm that the -53 A(TA)7TAA/A(TA)7TAA is not, while the 211AA is a risk factor for the development of neonatal hyperbilirubinemia in Taiwanese.

Prolonged unconjugated hyperbiliriubinemia in breast-fed male infants with a mutation of uridine diphosphate-glucuronosyl transferase.

OBJECTIVE: To test the hypothesis that a mutation in uridine diphosphate-glucuronosyl transferase 1A1 (UGT1A1) gene of breast-fed infants is a contributory factor to prolonged unconjugated hyperbilirubinemia. STUDY DESIGN: Of 125 breast-fed term infants, 35 infants had prolonged unconjugated hyperbilirubinemia; another 90 breast-fed neonates without prolonged jaundice were control infants. The polymerase chain reaction-restriction fragment length polymorphism method was used to detect the known variant sites (promoter area, nucleotides 211, 686, 1091, and 1456) of the UGT1A1 gene. RESULTS: Of 35 breast-fed infants with prolonged unconjugated hyperbilirubinemia, 29 had at least 1 mutation of the UGT1A1 gene. Variation at nucleotide 211 was most common. The percentages of the neonates carrying the variant nucleotide 211 were significantly different between the prolonged hyperbilirubinemia group and control neonates. Male breast-fed infants had a higher risk than female infants for prolonged hyperbilirubinemia. CONCLUSIONS: Male breast-fed neonates with a variant nucleotide 211 in UGT1A1 have a high risk for developing prolonged hyperbilirubinemia.

Integrated Counts of Carbohydrate-Active Protein Domains as Metabolic Readouts to Distinguish Probiotic Biology and Human Fecal Metagenomes.

Bowel microbiota is a "metaorgan" of metabolisms on which quantitative readouts must be performed before interventions can be introduced and evaluated. The study of the effects of probiotic Clostridium butyricum MIYAIRI 588 (CBM588) on intestine transplantees indicated an increased percentage of the "other glycan degradation" pathway in 16S-rRNA-inferred metagenomes. To verify the prediction, a scoring system of carbohydrate metabolisms derived from shotgun metagenomes was developed using hidden Markov models. A significant correlation (R = 0.9, p < 0.015) between both modalities was demonstrated. An independent validation revealed a strong complementarity (R = -0.97, p < 0.002) between the scores and the abundance of "glycogen degradation" in bacteria communities. On applying the system to bacteria genomes, CBM588 had only 1 match and ranked higher than the other 8 bacteria evaluated. The gram-stain properties were significantly correlated to the scores (p < 5 × 10-4). The distributions of the scored protein domains indicated that CBM588 had a considerably higher (p < 10-5) proportion of carbohydrate-binding modules than other bacteria, which suggested the superior ability of CBM588 to access carbohydrates as a metabolic driver to the bowel microbiome. These results demonstrated the use of integrated counts of protein domains as a feasible readout for metabolic potential within bacteria genomes and human metagenomes.

Laparoscopic-assisted colonoscopic polypectomy for juvenile polyp in children: a new minimal-invasive therapeutic approach.

An 8-year-old boy was hospitalized with fresh bloody stool passage for 1 week. He underwent colonoscopy that revealed 1 large polyp in the rectosigmoid junction. The polyp was too large to be encircled by the snare. Laparoscopic-assisted colonoscopic polypectomy was performed successfully to remove this large polyp without the need for segmental resections. This patient treated using this technique were discharged 2 days after the procedure and returned to full activity within 3 to 4 days. There were no complications.

Predictive value of clinical features in differentiating group A beta-hemolytic streptococcal pharyngitis in children.

Identifying children with acute pharyngitis caused by group A beta-hemolytic Streptococcus (GABHS) is an important task for pediatricians. This study examined the value of certain clinical symptoms and signs in predicting a positive culture result. A total of 442 children who presented at the outpatient department with pharyngeal erythema were enrolled. The clinical features of patients with positive throat cultures for GABHS were compared to those with negative culture results. Throat cultures were positive for GABHS in 120 (27%) patients. Patients aged between 5 and 10 years had a higher prevalence of GABHS pharyngitis. Significant differences between the groups with and without GABHS pharyngitis were noted for the presence of sore throat (p < 0.001), tonsillar swelling (p < 0.001), anterior cervical adenopathy (p = 0.004), and scarlatiniform rash (p < 0.001), but not for the presence of fever, cough, rhinorrhea, abdominal pain, headache, tonsillar exudate, or palatal petechiae. Despite these strong associations, none of these symptoms or signs had both high sensitivity and specificity, and the positive predictive values of these individual findings were never greater than 50%. The results indicate that diagnosis based on clinical grounds alone is unreliable although there are certain individual symptoms and signs that are associated with GABHS pharyngitis. These symptoms and signs may be helpful in modifying estimates of probability of infection with GABHS. Throat cultures in suspected patients remain mandatory.

Epidemiological and clinical features of group A Streptococcus pharyngitis in children.

In order to understand the prevalence of childhood streptococcal pharyngitis, isolation of group A Streptococcus (GAS) was attempted from throat swabs of pharyngitis patients. Children aged between 1 and 15 years presenting to the outpatient department with pharyngeal erythema were prospectively enrolled in the study. Demographic data and presenting symptoms and signs for each patient were recorded and a throat swab was taken. Of 1175 throat cultures obtained, GAS was isolated in 252 cases (21.4%). Of these, 142 (56.3%) were boys and 110 (43.7%) girls. A higher proportion of boys was found with GAS pharyngitis (1.29: 1). The mean age of GAS culture-positive patients was 7.8 +/- 2.3 years old. Patients aged between 6 and 11 years were more prevalent in GAS pharyngitis. Ninety (35.7%) of our GAS pharyngitis patients occurred between March and May. A second smaller peak occurred between October and December. The following factors showed independent positive correlation with GAS infection: sore throat (p < 0.001), no coryza (p = 0.011), tonsillar swelling (p < 0.001), anterior cervical adenopathy (p = 0.029) and scarlatiniform rash (p < 0.001). However, GAS was found in less than half of the patients who had these clinical manifestations. In conclusion, pharyngeal infection with GAS in children is not uncommon. The prevalence of GAS pharyngitis is related to patient gender, age, and month of the year. Diagnosis of GAS pharyngitis based on clinical features alone is unreliable.

Genetic variants in GCKR and PNPLA3 confer susceptibility to nonalcoholic fatty liver disease in obese individuals.

BACKGROUND: A genome-wide association study identified variants in or near patatin-like phospholipase domain-containing-3 (PNPLA3), neurocan (NCAN), lysophospholipase-like 1 (LYPLAL1), glucokinase regulatory protein (GCKR), and protein phosphatase 1 regulatory subunit 3b (PPP1R3B) that were strongly associated with nonalcoholic fatty liver disease (NAFLD) in adults of European ancestry. OBJECTIVE: We examined these genetic variants in obese children and tested whether their effects on NAFLD are significant in the Taiwanese Han Chinese population. DESIGN: We genotyped PNPLA3 rs738409, NCAN rs2228603, LYPLAL1 rs12137855, GCKR rs780094, and PPP1R3B rs4240624 in 797 obese children aged 7-18 y. NAFLD was identified by liver ultrasonography. We analyzed the effect of these genetic variants on NAFLD. RESULTS: NAFLD was identified in 24% of the recruited obese children. We found significant associations with NAFLD at variants in PNPLA3 and GCKR but not in NCAN, LYPLAL1, and PPP1R3B. Multiple logistic regression analysis showed that, after control for the effects of age- and sex-adjusted body mass index, waist-to-hip ratio, sex, and PNPLA3 rs738409 polymorphism, the variant GCKR rs780094 TT genotype independently increased the OR of NAFLD by 1.997 (95% CI: 1.196, 3.335; P = 0.008) compared with the CC genotype. Subjects with the variant GCKR rs780094 TT genotype had a higher mean serum alanine aminotransferase concentration than did those with the CC genotype (30.8 ± 34.7 compared with 22.2 ± 18.6 IU/L; P = 0.01). CONCLUSIONS: By studying the genetic variants of obese Taiwanese children, we confirmed that the genetic variants in GCKR rs780094 and PNPLA3 rs738409, but not in NCAN rs2228603, LYPLAL1 rs12137855, and PPP1R3B rs4240624, are associated with an increased risk of NAFLD. GCKR and PNPLA3 variants are the common genetic factors that may confer susceptibility to NAFLD in obese individuals across multiple ethnic groups.

A common variant in the peroxisome proliferator-activated receptor-γ coactivator-1α gene is associated with nonalcoholic fatty liver disease in obese children.

BACKGROUND: The single nucleotide polymorphism in the peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α gene (PPARGC1A) was identified to be associated with nonalcoholic fatty liver disease (NAFLD) in adults. The PPARGC1A gene encodes PGC-1α, which regulates cellular energy metabolism. OBJECTIVE: We aimed to test the hypothesis that the PPARGC1A rs8192678 risk A allele would influence the risk of NAFLD in obese children. DESIGN: We genotyped PPARGC1A rs8192678 and PNPLA3 rs738409 in 781 obese children aged 7-18 y. NAFLD was determined by ultrasonography. We evaluated the independent influence of the PPARGC1A rs8192678 risk A allele on pediatric NAFLD after control for the effect of the PNPLA3 rs738409 polymorphism. RESULTS: A total of 23.3% of the recruited obese children had NAFLD. PNPLA3 rs738409 increased the OR of NAFLD by 1.622 (95% CI: 1.071, 2.457; P = 0.023) in subjects with GC alleles and 2.659 (95% CI: 1.509, 4.686; P < 0.001) for GG alleles, as compared with CC alleles. After control for the effects of age- and sex-adjusted BMI, sex, and PNPLA3 rs738409 polymorphism, the PPARGC1A rs8192678 risk A allele was an independent risk factor for developing NAFLD, with an OR of 1.740 (95% CI: 1.149, 2.637; P = 0.009). Subjects with the PPARGC1A rs8192678 risk A allele had an increase in the mean serum alanine aminotransferase concentration of 5.2 IU/L, as compared with subjects without this allele (P = 0.011). CONCLUSION: The PPARGC1A rs8192678 risk A allele is associated with an increased risk of NAFLD, independent of the effect of the PNPLA3 rs738409 polymorphism in our population of obese Taiwanese children.