Genetic factors in physical growth and development and their relationship to subsequent health outcomes

Infant intakes of human milk branched chain amino acids are negatively associated with infant growth and influenced by maternal body mass index

BACKGROUND

Branched-chain amino acids (BCAAs: isoleucine, leucine, and valine) and aromatic amino acids (AAAs: phenylalanine and tyrosine) are hypothesized to influence early-life obesity risk.

OBJECTIVE

To assess HM free amino acid (AA) concentrations and infant intakes of HM AAs from women with obesity (OB) compared to those with normal weight (NW) and determine the relationships between HM AA consumption and infant growth.

METHODS

HM samples were collected at 0.5 (n = 151), 2 (n = 129), and 6 (n = 93) months postpartum from mothers with NW (body mass index [BMI] = 18.5-24.9 kg/m² ) and OB (BMI > 30 kg/m² ). HM AAs were quantified via mass spectrometry. Infant HM intake, anthropometrics and body composition were assessed. Linear mixed-effects models (LMEM) examined the relationships between maternal BMI and HM AA intakes, and HM AA intake and infant growth over the first 6 months postpartum after adjusting for maternal and infant characteristics.

RESULTS

Maternal BMI was positively associated with infant intakes of isoleucine, leucine, and AAAs across timepoints. HM AA intakes were positively associated with weight-for-length z-score, fat mass index, and fat-free mass index in infants (p < 0.05).

CONCLUSIONS

Maternal BMI led to differences in HM AA composition, which was associated with infant body composition.

People Are Taller in Countries With Better Environmental Conditions

Background: Height is considered an indicator of health and well-being of an individual and population. Height variation results from a complex interaction of genetic, environmental, socioeconomic, and cultural influences. In order to understand the contribution of environmental stress associated with the child's growth, we correlated indicators of a stressful environment with adult height. Methods: We utilized seven equally weighted indicators of a stressful environment: homicide rates, GDP per capita, income inequality (GINI index), corruption perception index (CPI), unemployment rate, urban air pollution, and life expectancy (LE). Data on male and female height by country from 1992 to 1996 were obtained from the NCD Risk Factor Collaboration dataset. We assessed separately data from the 31 member countries of the Organization for Economic Co-operation and Development (OECD). In order to establish whether the indicators reflected a single conceptual dimension, we conducted an exploratory analysis and principal component analysis (PCA) with orthogonal transformation of the original variables. The relationships between male and female heights and the z-transformed principal components: Quality of life (QoL) and the Social factor (SF) that were derived after the PCA was assessed. Results: Male and female heights strongly correlated (p < 0.0001) with each of the seven indicators. In the PCA, the indicators clustered into "Quality of Life" factors (QoL), which comprised the CPI, GDP, air pollution, LE, and "Social factors" (SF), which comprised homicide rate and GINI index. For males and females, the average height by country strongly correlated with QoL (p < 0.0001) and SF (p < 0.0001). Within OECD countries, male and female height strongly and negatively correlated with the SF, but not with QoL. Conclusion: Growth attenuation is a tradeoff adaptive response: a calorie used for growth cannot be used for fighting stress. Here we show that: (1) Adult height, when used as a measure of child's growth, is an indicator of a stressful environment in context with the genetic background and spatial factors; (2) Stressful QoL factors and the SF exert a greater effect on men's height than women's height; and (3) The ranking of the indicators of short stature are income inequality > air pollution > GDP > CPI > homicide rate > LE > unemployment.

Differences in the auxological characters of children with short stature - Differential diagnostic possibilities of hypothyreosis

This study aimed to define the differences in growth characteristics in the three most frequent causes of growth retardation - growth hormone deficiency, hypothyreosis and constitutional delay of growth and development - in order to provide diagnostic means for distinguishing these disorders. The study included 166 children with growth disorders aged 4-18 years. The height for age, the bone age using the TW3 method, the predicted height as the target height and the current prediction using the TW3 method were studied. For bone age, the radius, ulna and short bones compartment (RUS) and carpal bones (CARP) were evaluated separately and the difference in their delay in relation to chronological age (ΔBA_RUS_CARP) was determined. The relationship of the studied variables with sex and the underlying diagnosis was tested and the relationship of hypothyreosis and growth data was estimated. The model was tested on the growth data of 104 randomly selected patients with a growth disorder. The largest significant distinction was demonstrated by the difference ΔBA_RUS_CARP in hypothyreosis. The created linear regression model was highly statistically significant (χ² = 19.4, p < 0.0001) and showed high selectivity (0.609, 95% CI 0.409; 0.808) as well as high specificity (0.864, 95% CI 0.781; 0.946). The clinical validity of the model demonstrated a 61% predictive value for the detection and an 81% successful specification of hypothyreosis. The study demonstrated the possibility of distinguishing suspected hypothyreosis from other causes of growth retardation based on differences in severity of the ossification delay in skeletal compartments of the hand.

Factors influencing growth hormone levels of Bali cattle in Bali, Nusa Penida, and Sumbawa Islands, Indonesia

AIM

Bali cattle (Bos javanicus) are an Indonesian's native cattle breed that distributed in Asia to Australia. The scientific literature on these cattle is scarce. The growth hormone (GH) of Bali cattle is investigated from three separated islands, namely, Bali, Nusa Penida, and Sumbawa.

MATERIALS AND METHODS

Forty plasma samples were collected from each island, and the GH was measured using a commercial enzyme-linked immunosorbent assay kit. The data were analyzed based on the origin, sex, and cattle raising practices.

RESULTS

We found that the GH level (bovine GH [BGH]) of animal kept in stall 1.72±0.70 µg/ml was higher than free-grazing animal 1.27±0.81 µg/ml. The GH level was lower in female (1.22±0.62 µg/ml) compared to male animals (1.77±0.83 µg/ml).

CONCLUSION

We conclude that the level of BGH in Bali cattle was low and statistically equal from all origins. The different level was related to sex and management practices. Further validation is needed through observing the growth rate following BGH administration and discovering the inbreeding coefficient of the animal in Indonesia.

Small-quantity, lipid-based nutrient supplements provided to women during pregnancy and 6 mo postpartum and to their infants from 6 mo of age increase the mean attained length of 18-mo-old children in semi-urban Ghana: a randomized controlled trial

BACKGROUND

Childhood stunting usually begins in utero and continues after birth; therefore, its reduction must involve actions across different stages of early life.

OBJECTIVE

We evaluated the efficacy of small-quantity, lipid-based nutrient supplements (SQ-LNSs) provided during pregnancy, lactation, and infancy on attained size by 18 mo of age.

DESIGN

In this partially double-blind, individually randomized trial, 1320 women at ≤20 wk of gestation received standard iron and folic acid (IFA group), multiple micronutrients (MMN group), or SQ-LNS (LNS group) daily until delivery, and then placebo, MMNs, or SQ-LNS, respectively, for 6 mo postpartum; infants in the LNS group received SQ-LNS formulated for infants from 6 to 18 mo of age (endline). The primary outcome was child length by 18 mo of age.

RESULTS

At endline, data were available for 85% of 1228 infants enrolled; overall mean length and length-for-age z score (LAZ) were 79.3 cm and -0.83, respectively, and 12% of the children were stunted (LAZ <-2). In analysis based on the intended treatment, mean ± SD length and LAZ for the LNS group (79.7 ± 2.9 cm and -0.69 ± 1.01, respectively) were significantly greater than for the IFA (79.1 ± 2.9 cm and -0.87 ± 0.99) and MMN (79.1 ± 2.9 cm and -0.91 ± 1.01) groups (P = 0.006 and P = 0.009, respectively). Differences were also significant for weight and weight-for-age z score but not head or midupper arm circumference, and the prevalence of stunting in the LNS group was 8.9%, compared with 13.7% in the IFA group and 12.9% in the MMN group (P = 0.12). In analysis based on actual supplement provided at enrollment, stunting prevalences were 8.9% compared with 15.1% and 11.5%, respectively (P = 0.045).

CONCLUSION

Provision of SQ-LNSs to women from pregnancy to 6 mo postpartum and to their infants from 6 to 18 mo of age may increase the child's attained length by age 18 mo in similar settings. This trial was registered at clinicaltrials.gov as NCT00970866.

DNA methyltransferase candidate polymorphisms, imprinting methylation, and birth outcome

Background

Birth weight and prematurity are important obstetric outcomes linked to lifelong health. We studied a large birth cohort to look for evidence of epigenetic involvement in birth outcomes.

Methods

We investigated the association between birth weight, length, placental weight and duration of gestation and four candidate variants in 1,236 mothers and 1,073 newborns; DNMT1 (rs2162560), DNMT3A (rs734693), DNMT3B (rs2424913) and DNMT3L (rs7354779). We measured methylation of LINE1 and the imprinted genes, PEG3, SNRPN, and IGF2, in cord blood.

Results

The minor DNMT3L allele in the baby was associated with higher birth weight (+54 95% CI 10,99 g; p = 0.016), birth length (+0.23 95% CI 0.04,0.42 cm; p = 0.017), placental weight, (+18 95% CI 3,33 g; p = 0.017), and reduced risk of being in the lowest birth weight decile (p = 0.018) or requiring neonatal care (p = 0.039). The DNMT3B minor allele in the mother was associated with an increased risk of prematurity (p = 0.001). Placental size was related to PEG3 (p<0.001) and IGF2 (p<0.001) methylation. Birth weight was related to LINE1 and IGF2 methylation but only at p = 0.052. The risk of requiring neonatal treatment was related to LINE1 (p = 0.010) and SNRPN (p = 0.001) methylation. PEG3 methylation was influenced by baby DNMT3A genotype (p = 0.012) and LINE1 by baby 3B genotype (p = 0.044). Maternal DNMT3L genotype was related to IGF2 methylation in the cord blood but this effect was only seen in carriers of the minor frequency allele (p = 0.050).

Conclusions

The results here suggest that epigenetic processes are linked birth outcome and health in early life. Our emerging understanding of the role of epigenetics in health and biological function across the lifecourse suggests that these early epigenetic events could have longer term implications.

Rat Mcs1b is concordant to the genome-wide association-identified breast cancer risk locus at human 5q11.2 and MIER3 is a candidate cancer susceptibility gene

Low-penetrance alleles associated with breast cancer risk have been identified in population-based studies. Most risk loci contain either no or multiple potential candidate genes. Rat mammary carcinoma susceptibility 1b (Mcs1b) is a quantitative trait locus on RN02 that confers decreased susceptibility when Copenhagen (COP)-resistant alleles are introgressed into a Wistar Furth (WF)-susceptible genome. Five WF.COP congenic lines containing COP RN02 segments were compared. One line developed an average of 3.4 ± 2.0 and 5.5 ± 3.6 mammary carcinomas per rat ± SD when females were Mcs1b-resistant homozygous and Mcs1b heterozygous, respectively. These phenotypes were significantly different from susceptible genotype littermates (7.8 ± 3.1 mean mammary carcinomas per rat ± SD, P = 0.0001 and P = 0.0413, respectively). All other congenic lines tested were susceptible. Thus, Mcs1b was narrowed to 1.8 Mb of RN02 between genetic markers ENSRNOSNP2740854 and g2UL2-27. Mammary gland-graft carcinoma susceptibility assays were used to determine that donor (P = 0.0019), but not recipient Mcs1b genotype (P = 0.9381), was associated with ectopic mammary carcinoma outcome. Rat Mcs1b contains sequence orthologous to human 5q11.2, a breast cancer susceptibility locus identified in multiple genome-wide association studies. Human/rat MAP3K1/Map3k1 and mesoderm induction early response (MIER; MIER3)/MIER3 are within these orthologous segments. We identified MIER3 as a candidate Mcs1b gene based on 4.5-fold higher mammary gland levels of MIER3 transcripts in susceptible compared with Mcs1b-resistant females. These data suggest that the human 5q11.2 breast cancer risk allele marked by rs889312 is mammary gland autonomous, and MIER3 is a candidate breast cancer susceptibility gene.

Effect of growth in infancy on body composition, insulin resistance, and concentration of appetite hormones in adolescence

BACKGROUND

High infancy weight gain is associated with increased body mass index (BMI) and insulin resistance (IR) in later life, but the association with later body composition has not been well explored. Appetite regulatory hormones may be programmed in early life, but data to support this are lacking.

OBJECTIVE

We investigated the effect of weight gain in infancy on body composition, IR, leptin, ghrelin, and adiponectin at 17 y of age.

DESIGN

This was an observational study of 95 term and appropriate-for-gestational-age infants. We measured weight at birth and 9 mo of age and, for a subgroup (n = 60), at 3 and 6 mo of age. Changes in weight SD scores from 0 to 9, 0 to 3, 3 to 6, and 6 to 9 mo of age were calculated. Follow-up examinations at 10 and 17 y of age included body fat (BF) assessment by dual-energy X-ray absorptiometry scanning. We measured serum leptin, ghrelin adiponectin, and IR at 17 y of age.

RESULTS

Weight gain from 0 to 9 mo of age was positively associated with BMI (P < 0.003), percentage BF (P < 0.05), and percentage trunk fat (TF) (P < 0.03) but not with percentage TF relative to total BF, in childhood and adolescence, and most of these effects were explained by growth from 0 to 3 mo of age. Weight gains from 0 to 9 and 0 to 3 mo of age were not related to IR or leptin but were negatively associated with ghrelin and adiponectin corrected for BF at 17 y of age.

CONCLUSION

Our findings suggest that high weight gain in infancy, especially from 0 to 3 mo of age, has a role in programming both BF and concentrations of ghrelin and adiponectin in adolescence, whereas there was no effect on IR or leptin in this study.

Ethnic differences in body composition and the associated metabolic profile: a comparative study between Asians and Caucasians

It is estimated that Asia will be the home of more than 100 million people with type 2 diabetes by the year of 2025. This region combines a high proportion of the world's population with rapidly rising diabetes prevalence rates. The increase in diabetes in Asia differs from that reported in other parts of the world: it has developed in a shorter time, in a younger age group, and in people with lower body-mass index (BMI). Studies reported that for the same BMI, Asians have a higher body fat percentage, a prominent abdominal obesity, a higher intramyocellular lipid and/or a higher liver fat content compared to Caucasians. These characteristics may contribute to a higher predisposition to insulin resistance at a lesser degree of obesity than Caucasians. The differences in body composition are more pronounced depending on the region. For the same BMI, among three major ethnic groups in Asia, Asian Indians have the highest body fat, followed by Malay and Chinese. Lower insulin sensitivity is already observed in Asian Indian adolescents with a higher body fat and abdominal obesity compared to Caucasian adolescents. In general, Asian adolescents share the same feature of body composition such as higher body subcutaneous fat, lower appendicular skeletal muscle and lower gynoid fat compared to Caucasian adolescents. This unfavourable body composition may predispose to the development of insulin resistance at later age. Genetics may play a role and the interaction with environmental factors (changes in lifestyle) could increase the risk of developing the metabolic syndrome.

Femoral head epiphysis growth and development among Chinese children aged 0-5 years

The aim of this study was to examine the pattern of femoral head epiphysis growth and development among Chinese children. Between January and December, 2007, we randomly sampled 1,450 healthy Chinese children (0-5 years old) from Hunan Provincial Children's Hospital in Changsha, Hunan, China. The diameter of femoral head epiphysis was measured by pelvic X-ray photography and processed by medical image processing software. The growth of femoral head epiphysis in girls was 2-3 months earlier than that in boys. The diameter of femoral head epiphysis increased with advancing age in both girls and boys, but the diameter of femoral head epiphysis in 2, 3, 4, 6, and 10-month-old girls was significantly larger than that in boys. Cubic regression equations between the diameter of femoral head epiphysis and age were created for boys and girls that could be used to predict the diameter of femoral head epiphysis. In conclusion, there was gender difference in femoral head epiphysis growth and development among Chinese children, and our prediction models will provide the guidance for early diagnosis of diseases related to the growth and development of the femoral head epiphysis.

Effects of UCP2 and UCP3 variants on the manifestation of overweight in Korean children

To investigate the associations of uncoupling protein (UCP)2 and UCP3 gene variants with overweight and related traits, we genotyped UCP2-866G>A, UCP2Ala55Val, and UCP3-55C>T in 737 Korean children and 732 adults and collected data regarding anthropometric status and blood biochemistry. Information concerning the children's lifestyles and dietary habits was collected. The UCP2-866G>A and UCP3-55C>T gene variants showed significant associations with BMI level, waist circumference, and body weight in the children but not in the adults. Compared with -866GG carriers, the -866GA and AA carriers showed a strong decreasing trend in the risk for overweight (odds ratio (OR), 0.67; 95% confidence interval (CI), 0.45-1.01; P = 0.053). In comparison with UCP3-55CC carriers, children carrying -55CT and TT showed a significant reduction in the risk of overweight (OR, 0.67; 95% CI, 0.46-0.98; P = 0.039). There was also evidence of interactions between the effects of the combined UCP2-UCP3 genotype and obesity-related metabolic traits. The greatest protective effect against overweight was seen in those with the combined genotype non-UCP2-866GG and non-UCP3-55CC, as compared with those carrying both UCP2-866GG and UCP3-55CC (OR,0.60; 95% CI, 0.38-0.95; P = 0.030). In the subgroup with a low level of physical activity, UCP3-55CC carriers had higher BMI values than UCP3-55T carriers (16.6 +/- 2.3 kg/m(2) vs. 16.1 +/- 1.9 kg/m(2), P = 0.016). Low physical activity may aggravate the susceptibility to overweight in UCP2-866GG and UCP3-55CC carriers.

Trait-specific tracking and determinants of body composition: a 7-year follow-up study of pubertal growth in girls

BACKGROUND

Understanding how bone (BM), lean (LM) and fat mass (FM) develop through childhood, puberty and adolescence is vital since it holds key information regarding current and future health. Our study aimed to determine how BM, LM and FM track from prepuberty to early adulthood in girls and what factors are associated with intra- and inter-individual variation in these three tissues.

METHODS

The study was a 7-year longitudinal cohort study. BM, LM and FM measured using dual-energy X-ray absorptiometry, self-reported dietary information, leisure time physical activity (LTPA) and other factors were assessed one to eight times in 396 girls aged 10 to 13 years (baseline), and in 255 mothers once.

RESULTS

The location of a girl's BM, LM and FM in the lower, middle or upper part of the sample distribution was established before puberty and tracked in its percentile of origin over 7 years (r = 0.72 for BM, r = 0.61 for LM, and r = 0.65 for FM all p < 0.001 first vs. last measurements' ranking). Seventy-three percent of those in the lowest quartile for BM and 69% for LM, and 79% of those in the highest quartile for FM at baseline remained in their quartile at 7-year follow-up. Heritability was estimated to contribute 69% of the total variance of the BM, 50% of the LM, and 57% of the FM. Besides body size, diet index (explaining 9% of variance), breast feeding duration (6%) and mother's BM (9%) predicted high BM. Diet index and high LTPA predicted high LM (24% and 14%, respectively), and low FM (25% and 12%, respectively), and low level of parental education predicted high FM (4%).

CONCLUSION

Individual levels of BM, LM and FM are established before puberty and track in a trait-specific manner until early adulthood. Girls who are prone to develop low BM and LM and high FM in adulthood can be identified in prepuberty. The developments of three components of body composition are inter-related during growth. BM was the most heritable trait while LM the most environmentally modifiable. Diet and physical activity played an important role in increasing LM and preventing the accumulation of excessive FM.