Cleft Laterality Dental Arch Relationship Outcomes for Children with Unilateral Cleft Lip and Palate in New Zealand.

OBJECTIVES: To investigate cleft laterality dental arch relationship outcomes of children with non-syndromic complete unilateral cleft lip and palate (UCLP) in New Zealand. DESIGN: A retrospective nationwide study. SETTINGS: Virtual 3D orthodontic study models collected prior to undertaking secondary alveolar bone grafting. PARTICIPANTS: A total of 104 patients with UCLP (L = 80: R = 24). OUTCOME MEASURES: Four calibrated assessors used the GOSLON Yardstick and 100 mm Visual Analogue Scale (VAS) to score the randomised models on 2 separate assessment sessions. Weighted Kappa were used to determine the intra/inter-rater reliability for the GOSLON and correlations for the VAS. RESULTS: Intra-rater reliability ranged from 0.57-0.88 (GOSLON) and 0.45-0.93 (VAS). Inter-rater reliability ranged from 0.62-0.86 (GOSLON) and 0.64-0.93 (VAS).GOSLON scores for the left UCLP were 31.2% for good/very good; 26.3% for fair; 42.5% for poor/very poor while the right UCLP scored 8.3% for good/very good; 37.5% for fair; 54.2% for poor/very poor. The mean VAS for left and right UCLP were 53.4 (sd 22.5) and 44.6 (sd 17.1) respectively. Neither the GOSLON nor VAS differences reached statistical significance (both P = .08). CONCLUSIONS: From a clinical perspective right UCLP had worse dental arch relationship outcomes, however, these differences failed to reach statistical significance. Further studies using larger sample sizes are required to determine if cleft laterality is an important consideration when investigating UCLP dental arch outcomes.

The relative importance of eating quality and carcass yield in determining beef carcass value.

Carcass value is a complex relationship with varying contributions between eating quality (MSA Index) and lean cut yield (LCY%). Bone-out data from 112 Bos taurus steer carcasses, grain finished for 100 days with a hormonal growth promotant were analyzed. Carcass values were calculated using 1) flat cut prices, 2) cut prices weighted for MSA grades, and 3) cut prices weighted for MSA grades for four high value primals. To extend the range in eating quality, analyses were re-run assuming no HGP implants. When all cuts were valued according to eating quality grade, the impact of the MSA Index and LCY% varied in their importance in determining carcass value. However, if only four high value cuts were harvested, carcass value was largely a function of LCY%. The importance of eating quality and carcass yield in determining carcass value was dependent upon the type of cattle, the cuts being harvested and the grade premiums/discounts realized.

Development and validation of the Safe Sleep Calculator to assess risk of sudden unexpected death in infancy.

We describe the development and validation of a Sudden Unexpected Death in Infancy (SUDI) risk assessment clinical tool. An initial SUDI risk assessment algorithm was developed from an individual participant data meta-analysis of five international SIDS/SUDI case-control studies. The algorithm was translated into a clinical web tool called the Safe Sleep Calculator, which was tested at the routine infant 6-week check-up in primary care clinics in New Zealand. Evidence was gathered through mixed-methods research to inform the revision of the algorithm and the clinical tool. The revised algorithm performance was validated on a new contemporary New Zealand SUDI case-control study dataset and the pilot population data set. The area under the Receiver Operator Characteristic (ROC) curve is 0.89, with a sensitivity of 83.0% and a specificity of 80.9% in the NZ infant population when 0.3 per 1000 live births or more risk is used to define 'at higher risk'. The Safe Sleep Calculator SUDI risk assessment tool provides individualized evidence-based specific SUDI prevention advice for every infant and enables the concentration of additional SUDI prevention efforts and resource for infants at higher risk.

Maternal Mid-Gestation Cytokine Dysregulation in Mothers of Children with Autism Spectrum Disorder.

Autism spectrum disorder (ASD) is a developmental disorder characterised by deficits in social interactions and communication, with stereotypical and repetitive behaviours. Recent evidence suggests that maternal immune dysregulation may predispose offspring to ASD. Independent samples t-tests revealed downregulation of IL-17A concentrations in cases, when compared to controls, at both 15 weeks (p = 0.02), and 20 weeks (p = 0.02), which persisted at 20 weeks following adjustment for confounding variables. This adds to the growing body of evidence that maternal immune regulation may play a role in foetal neurodevelopment.

The impact of different Hormonal Growth Promotants (HGP) on desmin degradation and collagen content of various muscles from pasture and feedlot finished steer carcasses.

The impacts of several hormonal growth promotants (HGP) on Warner-Bratzler Shear Force (WBSF), desmin degradation ratio (DDR) and collagen content (COLL) were assessed. Treatments within feedlot and pasture finished steer carcasses (n = 60, n = 40, respectively) were control (CON-100-F and CON-400-P), oestradiol HGPs (OES-100-F and OES-400-P) and trenbolone acetate/oestradiol HGPs (TBA+OES-100-F only). The longissimus lumborum (LL), gluteus medius (GM), infraspinatus (IS), semitendinosus (ST,) and the LL and biceps femoris (BF) were collected from feedlot and pasture finished steers, respectively. All muscles were aged between 3 and 35 days. The LL from TBA+OES-100-F carcasses had increased WBSF and decreased DDR, which varied in magnitude with ageing (P < 0.05). The GM from OES-100-F steers also had lower DDR (P < 0.05). The feedlot HGP treatments had no impact on the WBSF of the IS, ST or GM and no impact on COLL in the LL. The OES-400-P had no impact on WBSF, DDRor COLL for both muscles (P > 0.05).

Does a single adjustment in the meat standards Australia beef grading model cater for different hormonal growth promotant formulations?

This paper investigated whether a single Hormonal Growth Promotant (HGP) adjustment in the Meat Standards Australia (MSA) beef grading model adequately predicted consumer eating quality of beef from cattle treated with different HGP formulations. This paper used consumer sensory data from two experiments. In experiment one, a total of 300 steers were allocated to three treatments; control (CON-100-F), 100 day oestradiol only HGP (OES-100-F), or a combination of trenbolone acetate and oestradiol HGP (TBA+OES-100-F) and finished in a feedlot for 73 days. In experiment two, a total of 200 steers were allocated either control or 400 day oestradiol only HGP treatments and finished on pasture for 389 days. Steers were slaughtered by finishing regime and carcass traits recorded. The anterior and posterior portions of the m. longissimus lumborum (LL-A and LL-P, respectively) and m. gluteus medius (GM) were collected and aged for five or 35 days. Grilled meat samples were scored for tenderness, juiciness, liking of flavour and overall acceptability using untrained consumers. Sensory scores were weighted by 0.3. 0.1, 0.3 and 0.3, respectively and summed to calculate a meat quality (MQ4) score. Residual MQ4 scores were calculated (observed MQ4 minus the predicted MQ4 score). The MSA model accounts for varied impacts of different HGPs on eating quality through a single HGP adjustment, and indirect impacts on carcass traits. For the majority of the HGP treatment samples, the residual MQ4 scores were not different to zero (5/18), or were positive i.e. the MSA model under-predicted these samples (11/18). Under-prediction was predominately for 35 day aged (7/9) and GM HGP treatment samples (6/6) and was considered low, with the majority less than ±5 MQ4 units. Under-prediction could be considered as advantageous through providing an additional safeguard to protect the interests of the consumers, rather than if the model had over-predicted and resulted in a more negative eating quality experience than expected. Some over-prediction was observed in the CON-100-F and TBA+OES-100-F treatment samples, which may be due to factors such as genetic variation and/or production environment. Minimal bias was observed when residual MQ4 was regressed against predicted MQ4 for the range of feeding regimes, muscles, ageing periods and treatment groups. This study showed that a single HGP adjustment in the MSA beef grading model, combined with the indirect effects of the different HGP formulations on carcass traits, provided a reasonable prediction of meat eating quality for different HGP formulations.

Prediction of consumer palatability in beef using visual marbling scores and chemical intramuscular fat percentage.

With development of objective technologies that can predict chemical intramuscular fat percentage (IMF%), there is a need to understand the relationships between existing marbling traits, IMF% and eating quality. This study utilised historical carcass data (n = 9641 observations) from the Meat Standards Australia (MSA) industry research dataset and included MSA grading data, chemical IMF% data and weighted composite eating quality scores (MQ4). Several analyses were performed to assess the prediction of MQ4 by MSA marbling, M. longissimus thoracis et lumborum (striploin) IMF% and cut specific IMF%. Results demonstrated that there was similar precision between chemical IMF% (R2 = 0.32, RSE = 11.8) and MSA marbling (R2 = 0.28, RSE = 11.9) in the prediction of grilled 14 day aged striploin MQ4, with similar results across other cut by cook by days aged combinations. These results support the development of objective technologies that predict chemical IMF% in parallel with MSA marbling for carcass grading and the prediction of eating quality.

Exposure to antibiotics in the first 24 months of life and neurocognitive outcomes at 11 years of age.

RATIONALE: Antibiotics are commonly prescribed for infants. In addition to increasing concern about antibiotic resistance, there is a concern about the potential negative impact of antibiotics on the gut microbiota and health and development outcomes. OBJECTIVE: The aim of this study was to investigate the association between early life antibiotic exposure and later neurocognitive outcomes. METHODS: Participants were infants born to mothers enrolled in the probiotics study. The initial study was designed to evaluate the effect of two different probiotics on allergy outcomes in childhood. Antibiotic exposure was based on parent report and categorised according to the following timing of the first exposure: 0-6 months, 6-12 months, 12-24 months or not at all. At 11 years of age, children's neurocognitive outcomes were assessed using psychologist-administered, parent-report and self-report measures. The relationship between the timing of antibiotic exposure and neurocognitive outcomes was examined using regression models. RESULTS: Of the 474 participants initially enrolled, 342 (72%) children had a neurocognitive assessment at 11 years of age. After adjustment for mode of delivery, probiotic treatment group assignment, income and breastfeeding, children who had received antibiotics in the first 6 months of life had significantly lower overall cognitive and verbal comprehension abilities, increased risk of problems with metacognition, executive function, impulsivity, hyperactivity, attention-deficit hyperactivity disorder, anxiety and emotional problems. CONCLUSIONS: These results provide further evidence that early exposure to antibiotics may be associated with detrimental neurodevelopmental outcomes.

The Meat Standards Australia Index indicates beef carcass quality.

A simple index that reflects the potential eating quality of beef carcasses is very important for producer feedback. The Meat Standards Australia (MSA) Index reflects variation in carcass quality due to factors that are influenced by producers (hot carcass weight, rib fat depth, hump height, marbling and ossification scores along with milk fed veal category, direct or saleyard consignment, hormonal growth promotant status and sex). In addition, processor impacts on meat quality are standardised so that the MSA Index could be compared across time, breed and geographical regions. Hence, the MSA Index was calculated using achilles hung carcasses, aged for 5 days postmortem. Muscle pH can be impacted by production, transport, lairage or processing factors, hence the MSA Index assumes a constant pH of 5.6 and loin temperature of 7oC for all carcasses. To quantify the cut weight distribution of the 39 MSA cuts in the carcass, 40 Angus steers were sourced from the low (n=13), high (n=15) and myostatin (n=12) muscling selection lines. The left side of each carcass was processed down to the 39 trimmed MSA cuts. There was no difference in MSA cut distribution between the low and high muscling lines (P>0.05), although there were differences with nine cuts from the myostatin line (P<0.05). There was no difference in the MSA Index calculated using actual muscle percentages and using the average from the low and high muscling lines (R 2=0.99). Different cooking methods impacted via a constant offset between eating quality and carcass input traits (R 2=1). The MSA Index calculated for the four most commercially important cuts was highly related to the index calculated using all 39 MSA cuts (R 2=0.98), whilst the accuracy was lower for an index calculated using the striploin (R 2=0.82). Therefore, the MSA Index was calculated as the sum of the 39 eating quality scores predicted at 5 days ageing, based on their most common cooking method, weighted by the proportions of the individual cut relative to total weight of all cuts. The MSA Index provides producers with a tool to assess the impact of management and genetic changes on the predicted eating quality of the carcass. The MSA Index could also be utilised for benchmarking and to track eating quality trends at farm, supply chain, regional, state or national levels.

The impact of oestradiol only hormone growth promotants (HGPs) on the eating quality of pasture finished steer carcasses.

A total of 200 Bos indicus/Bos taurus cross steers were allocated to control (CON) and an oestradiol (OES) implant treatments and pasture finished for 389 days. Longissimus lumborum (LL) and gluteus medius (GM) samples were aged for 5 and 35 days. Live weight, carcass weight and ossification scores (P < 0.05) increased in OES relative to CON. The three-way interaction between treatment, days aged and muscle was significant (P < 0.05) for tenderness, overall liking and meat palatability, whereby the OES had lower scores relative to CON at 5 days in LL (P < 0.05), although the difference halved by 35 days. For the GM, OES scores at 5 days were lower than CON (P < 0.05), apart from like flavour, and differences reduced by 35 days. LL shear force was higher for OES at 5 days (P < 0.05), though not 35 days (P > 0.05), or the GM at 5 or 35 days (P > 0.05). OES samples had a higher calpastatin activity (P < 0.05) in the LL at 19 h post mortem.

The role for cyclic Glycine-Proline, a biological regulator of insulin-like growth factor-1 in pregnancy-related obesity and weight changes.

Cyclic Glycine-Proline (cGP) regulates the homeostasis of insulin-like growth factor (IGF)-1 function and cGP/IGF-1 ratio determines IGF-1 bioactivity in vitro and in vivo. Plasma IGF-1 represents largely inactive IGF-1 and weakly associated with human obesity and hypertension. We evaluated the regulatory role for cGP in pregnancy-related obesity and hypertension, and in obesity status between pregnancy and postpartum. Women were recruited in their first pregnancy. A cross-sectional study compared plasma concentration of cGP, IGF-1 and IGF binding protein (IGFBP)-3 in women with obesity and/or hypertension to normal controls 6-year postpartum using UPLC-MS and ELISA. A longitudinal study compared the changes of these peptides from 15-week gestation to 6-year post-partum in the women who remained normal weight, remained obese or changed to obese or to normal respectively. Study 1 is a cross-sectional study. The obese group had lower IGF-1(p = 0.001), higher cGP/IGF-1 ratio (p = 0.0055) and the hypertensive group had lower IGFBP-3 (p = 0.046) and cGP (p = 0.043) than the controls. Study 2 is a longitudinal study. Women with weight loss had increased cGP/IGF-1 ratio (p = 0.0026) and decreased IGFBP-3 (p = 0.0001) compared with women whose weight remained normal. Women with weight gain had lower IGFBP-3 (p less than 0.0001) only. Women who remained obese had increased cGP/IGF-1 ratio (p = 0.006) only. Increase in cGP/IGF-1 ratio is associated with obesity, but not hypertension. Changes of IGFBP-3 and/or cGP/IGF-1 ratio are associated with weight changes. The data suggest the role for cGP in obesity through autocrine regulation of IGF-1.

Smoking in pregnancy is a key factor for sudden infant death among Maori.

AIM: To examine the sudden unexpected death in infancy (SUDI) disparity between Maori and non-Maori in New Zealand. METHODS: A nationwide prospective case-control study ran from March 2012 to February 2015. Exposure to established SUDI risk factors was analysed to investigate the disparity experienced by Maori. Infant ethnicity was based on mother's ethnicity. Maori ethnicity was prioritised. Non-Maori includes Pacific, Asian, NZ European and Other. RESULTS: There were 137 cases and 649 controls. The Maori SUDI rate was 1.41/1000 live births compared to 0.53/1000 for non-Maori. Parents/caregivers of 132 cases (96%) and 258 controls (40%) were interviewed. Smoking in pregnancy was associated with an equally increased SUDI risk for Maori (adjusted OR = 8.11, 95% CI = 2.64, 24.93) and non-Maori (aOR = 5.09, 95% CI = 1.79, 14.47), as was bed-sharing (aOR = 3.66, 95% CI = 1.49, 9.00 vs aOR = 11.20, 95% CI = 3.46, 36.29). Bed-sharing prevalence was similar; however, more Maori controls smoked during pregnancy (46.7%) than non-Maori (22.8%). The main contributor relating to increased SUDI risk for Maori/non-Maori infants is the combination of smoking in pregnancy and bed sharing. CONCLUSION: The association between known SUDI risk factors, including bed sharing and/or smoking in pregnancy and SUDI risk, is the same regardless of ethnicity. Maori infants are exposed more frequently to both behaviours because of the higher Maori smoking rate.

The effect of packaging on consumer eating quality of beef.

This experiment examined 3 packaging systems: overwrap packaging using oxygen permeable film (OWP); vacuum skin packaging (VSP) and modified atmosphere packaging (MAP, 80%O2 and 20%CO2) on consumer sensory. Three primals from 48 carcasses were aged in vacuum packs for 5, 12 or 40 days. Steaks from longissimus lumborum, gluteus medius and psoas major muscles were packed in OWP, VSP and MAP for 9 days. Untrained consumers scored grilled steaks for tenderness, juiciness, liking of flavour and overall acceptability. Steaks in MAP had 10-12 points lower sensory scores (on a 100 point scale) compared to the OWP, or VSP systems (P < 0.001). The packaging effect was independent of days aging and muscle. It was concluded that high oxygen MAP has the potential to be included as an input variable in the Meat Standards Australia beef grading model. This would be contingent upon research into when the MAP effect occurred and the effect of using different gas mixtures on eating quality.

Do extended transport times and rest periods impact on eating quality of beef carcasses?

The experiment tested the effect of four extended transport treatments on sensory and objective meat quality in beef. A total of 343 steers (88 steers from each of three properties and 79 from a fourth property) were allocated to four treatments including a 12 hour transport time (T12), 24 hour transport time (T24), 24 h as 12 hour transport time, a 12 hour rest, with a further 12 hour transport (T12 ~ T12), 36 hour transport treatment (T36). Within property departure times of treatments were staggered to arrive at the abattoir together. There were no significant transport effects (P > .05) on live animal, carcass traits, consumer sensory scores, and objective meat quality of the longissimus lumborum. There was large between property variation in the proportions of carcasses excluded from grading on the basis of low ribfat, high ultimate pH and dark meat color scores. Variation in these traits was not associated with transport treatments and was likely related to variation in on-farm factors.

Effects of an acute therapeutic or rewarding dose of amphetamine on acquisition of Pavlovian autoshaping and ventral striatal dopamine signaling.

Rewarding doses of amphetamine increase the amplitude, duration, and frequency of dopamine transients in the ventral striatum. Debate continues at the behavioral level about which component of reward, learning or incentive salience, is signaled by these dopamine transients and thus altered in addiction. The learning hypothesis proposes that rewarding drugs result in pathological overlearning of drug-predictive cues, while the incentive sensitization hypothesis suggests that rewarding drugs result in sensitized attribution of incentive salience to drug-predictive cues. Therapeutic doses of amphetamine, such as those used to treat attention-deficit hyperactivity disorder, are hypothesized to enhance the ventral striatal dopamine transients that are critical for reward-related learning and to enhance Pavlovian learning. However, the effects of therapeutic doses of amphetamine on Pavlovian learning are poorly understood, and the effects on dopamine transients are completely unknown. We determined the effects of an acute pre-training therapeutic or rewarding amphetamine injection on the acquisition of Pavlovian autoshaping in the intact rat. We also determined the effects of these doses on electrically evoked transient-like dopamine signals using fast-scan cyclic voltammetry in the anesthetized rat. The rewarding dose enhanced the amplitude and duration of DA signals, caused acute task disengagement, impaired learning for several days, and triggered incentive sensitization. The therapeutic dose produced smaller enhancements in DA signals but did not have similar behavioral effects. These results underscore the necessity of more studies using therapeutic doses, and suggest a hybrid learning/incentive sensitization model may be required to explain the development of addiction.

Effect of Lactobacillus rhamnosus HN001 in Pregnancy on Postpartum Symptoms of Depression and Anxiety: A Randomised Double-blind Placebo-controlled Trial.

BACKGROUND: Probiotics may help to prevent symptoms of anxiety and depression through several putative mechanisms. OBJECTIVE: The aim of this study was to evaluate the effect of Lactobacillus rhamnosus HN001 (HN001) given in pregnancy and postpartum on symptoms of maternal depression and anxiety in the postpartum period. This was a secondary outcome, the primary outcome being eczema in the offspring at 12months of age. DESIGN, SETTING, PARTICIPANTS: A randomised, double-blind, placebo-controlled trial of the effect of HN001 on postnatal mood was conducted in 423 women in Auckland and Wellington, New Zealand. Women were recruited at 14-16weeks gestation. INTERVENTION: Women were randomised to receive either placebo or HN001 daily from enrolment until 6months postpartum if breastfeeding. OUTCOME MEASURES: Modified versions of the Edinburgh Postnatal Depression Scale and State Trait Anxiety Inventory were used to assess symptoms of depression and anxiety postpartum. TRIAL REGISTRATION: Australia NZ Clinical Trials Registry: ACTRN12612000196842. FINDINGS: 423 women were recruited between December 2012 and November 2014. 212 women were randomised to HN001 and 211 to placebo. 380 women (89.8%) completed the questionnaire on psychological outcomes, 193 (91.0%) in the treatment group and 187 (88.6%) in the placebo group. Mothers in the probiotic treatment group reported significantly lower depression scores (HN001 mean=7·7 (SD=5·4), placebo 9·0 (6·0); effect size -1·2, (95% CI -2·3, -0·1), p=0·037) and anxiety scores (HN001 12·0 (4·0), placebo 13·0 (4·0); effect size -1·0 (-1·9, -0·2), p=0·014) than those in the placebo group. Rates of clinically relevant anxiety on screening (score>15) were significantly lower in the HN001 treated mothers (OR=0·44 (0·26, 0·73), p=0·002). INTERPRETATION: Women who received HN001 had significantly lower depression and anxiety scores in the postpartum period. This probiotic may be useful for the prevention or treatment of symptoms of depression and anxiety postpartum. FUNDING SOURCE: Health Research Council of New Zealand (11/318) and Fonterra Co-operative Group Ltd.

The relationship between maternal 25-hydroxyvitamin D status in pregnancy and childhood adiposity and allergy: an observational study.

BACKGROUND: Vitamin D insufficiency (defined as <75 nmol l-1) is widespread among pregnant women around the world and has been proposed to influence offspring outcomes in childhood and into adult life, including adiposity and allergy. Disorders, including asthma and eczema, are on the rise among children. Our aim was to investigate the relationship between maternal 25-hydroxyvitamin D status in pregnancy and offspring adiposity, asthma and eczema in childhood. SUBJECTS AND METHODS: Maternal 25-hydroxyvitamin D concentrations were analysed in serum samples collected at 15 weeks' gestation from 1710 participants of the prospective Screening for Pregnancy Endpoints cohort study. The offspring of 1208 mothers were followed up at age 5-6 years. Data collected included height, weight, percentage body fat (PBF, measured by bioimpedance) and history of asthma and eczema. Multivariable analysis controlled for maternal body mass index (BMI), age and sex of the child and season of serum sampling. RESULTS: Complete data were available for 922 mother-child pairs. Each 10 nmol l-1 increase in maternal 25-hydroxyvitamin D concentration at 15 weeks' gestation was associated with a decrease in offspring PBF of 0.2% (95% confidence interval 0.04-0.36%, P=0.01) after adjustment for confounders but was not related to child BMI z-score. Maternal mean (±s.d.) 25-hydroxyvitamin D concentration was similar in children who did and did not have asthma (71.7±26.1 vs 73.3±27.1 nmol l-1, P=0.5), severe asthma (68.6±28.6 vs 73.3±26.8 nmol l-1, P=0.2) and eczema (71.9±27.0 vs 73.2±27.0 nmol l-1, P=0.5). CONCLUSIONS: The finding of a relationship between maternal vitamin D status and adiposity in childhood is important, particularly because vitamin D insufficiency in pregnancy is highly prevalent. The association between maternal vitamin D supplementation in pregnancy and adiposity in the offspring merits examination in randomised controlled trials.

Dopamine transporter (DAT1/SLC6A3) polymorphism and the association between being born small for gestational age and symptoms of ADHD.

Being small for gestational age (SGA) has been established as a risk factor for Attention Deficit Hyperactivity Disorder (ADHD). Likewise, several molecular genetic studies have found a link between DAT1 and ADHD. This study investigated whether SGA moderates the effect of dopamine transporter gene variants on the risk of ADHD. A total of 546 children of European descent were genotyped at age 11 for seven DAT1 SNPs (rs6347, rs11564774, rs40184, rs1042098, rs2702, rs8179029 and rs3863145). The Strengths and Difficulties Questionnaire was used to measure symptoms of ADHD at ages 3.5, 7 and 11. We found significant gene-environment interactions between birth weight and DAT1 SNPs (rs6347, rs40184, rs1042098, rs3863145) on ADHD symptoms at 3.5 years only. Results suggest that genotypic variation of DAT1 may confer a relative protective effect against ADHD in SGA individuals. This study supports the idea that being born SGA moderates the effect of the DAT1 gene on ADHD symptoms in the preschool years and may help to explain some of the heterogeneity in ADHD outcomes.