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Author(s): Wessells, K Ryan; Arnold, Charles D; Stewart, Christine P; Prado, Elizabeth L; Abbeddou, Souheila; Adu-Afarwuah, Seth; Arnold, Benjamin F; Ashorn, Per; Ashorn, Ulla; Becquey, Elodie; Brown, Kenneth H; Byrd, Kendra A; Campbell, Rebecca K; Christian, Parul; Fernald, Lia CH; Fan, Yue-Mei; Galasso, Emanuela; Hess, Sonja Y; Huybregts, Lieven; Jorgensen, Josh M; Kiprotich, Marion; Kortekangas, Emma; Lartey, Anna; Le Port, Agnes; Leroy, Jef L; Lin, Audrie; Maleta, Kenneth; Matias, Susana L; Mbuya, Mduduzi NN; Mridha, Malay K; Mutasa, Kuda; Naser, Abu Mohd; Paul, Rina R; Okronipa, Harriet; Ouedraogo, Jean-Bosco; Pickering, Amy J; Rahman, Mahbubur; Schulze, Kerry; Smith, Laura E; Weber, Ann M; Zongrone, Amanda; Dewey, Kathryn G | Abstract: ABSTRACTBackgroundSmall-quantity lipid-based nutrient supplements (SQ-LNS) have been shown to reduce the prevalence of anemia and iron deficiency among infants and young children, but effects on other micronutrients are less well known. Identifying subgroups who may experience greater benefits from SQ-LNS, or who are more likely to respond to the intervention, may facilitate the development of public health policies and programs.ObjectiveOur objective was to identify study-level and individual-level modifiers of the effect of SQ-LNS on child hematological and micronutrient status outcomes.MethodsWe conducted a two-stage meta-analysis of individual participant data from 13 randomized controlled trials of SQ-LNS provided to children 6 to 24 months of age in low- and middle-income countries (n = 15,946). Outcomes were hemoglobin (Hb), inflammation-adjusted plasma ferritin, soluble transferrin receptor, zinc, retinol and retinol binding protein (RBP), and erythrocyte zinc protoporphyrin, and respective dichotomous outcomes indicative of anemia and micronutrient deficiency. We generated study-specific estimates of SQ-LNS vs. control, including main effects and subgroup estimates for individual-level effect modifiers, and pooled the estimates using fixed-effects models. We used random effects meta-regression to examine potential study-level effect modifiers.ResultsProvision of SQ-LNS decreased the prevalence of anemia (Hb l 110 g/L) by 16% (relative reduction), iron deficiency (plasma ferritin l 12 µg/L) by 56% and iron deficiency anemia (IDA; Hb l 110 g/L and plasma ferritin l 12 µg/L) by 64%. We observed positive effects of SQ-LNS on hematological and iron status outcomes within all subgroups of the study-level and individual-level effect modifiers, but effects were larger in certain subgroups. For example, effects of SQ-LNS on anemia and iron status were greater in trials that provided SQ-LNS for g 12 months and provided 9 mg/d vs. l 9 mg iron/d, and among later-born (vs. first-born) children. There was no effect of SQ-LNS on plasma zinc or retinol, but there was a 7% increase in plasma RBP and a 56% reduction in vitamin A deficiency (RBP l 0.70 µmol/L), with little evidence of effect modification by individual-level characteristics.ConclusionsSQ-LNS provided to infants and young children 6-24 months of age can substantially reduce the prevalence of anemia, iron deficiency, and IDA across a range of individual, population and study design characteristics. Policy-makers and program planners should consider SQ-LNS within intervention packages to prevent anemia and iron deficiency. This study was registered at www.crd.york.ac.uk/PROSPERO as CRD42020156663.

In this study, the effect of ripening stage (R), cultivar (C), bunch type (T), and location (L) on the variability of provitamin A carotenoids (pVACs) in 16 plantain cultivars grown in Cameroon and Gabon was investigated. For the sixteen plantain cultivars, fruits were collected at stages 1 (unripe), 5 (ripe), and 7 (overripe) from three different bunch types (French, False Horn, and True Horn) across 13 locations in Cameroon and Gabon. For all cultivars, the highest concentration of carotenoids was found in ripe pulp (p < 0.05). For bunch type, a higher level of pVACs was observed in the French type compared with the False Horn and True Horn types at all ripening stages. In addition, the concentration of pVACs at each ripening stage varied greatly across locations. In both countries, the interaction between the four factors, particularly between R × C, R × T, R × L, R × C × L, and R × T × L, contributed significantly (p < 0.05) to the variability of pVACs in plantain. Daily consumption of 100 g of ripe plantain could meet 36.2–101.7 % of the dietary reference intakes (DRIs) for children 1–5 years old, 20.7–58.1 % for adult women, and 16.1–45.2 % for adult men. These findings can serve as a guide to reducing vitamin A deficiency (VAD) in Africa. ispartof: Journal Of Food Composition And Analysis vol:94 pages:1-17 status: published

LOXL1 (lysyl oxidase-like 1) has been identified as the major effect locus in pseudoexfoliation (PEX) syndrome, a fibrotic disorder of the extracellular matrix and frequent cause of chronic open-angle glaucoma. However, all known PEX-associated common variants show allele effect reversal in populations of different ancestry, casting doubt on their biological significance. Based on extensive LOXL1 deep sequencing, we report here the identification of a common non-coding sequence variant, rs7173049A>G, located downstream of LOXL1, consistently associated with a decrease in PEX risk (odds ratio, OR = 0.63; P = 6.33 × 10−31) in nine different ethnic populations. We provide experimental evidence for a functional enhancer-like regulatory activity of the genomic region surrounding rs7173049 influencing expression levels of ISLR2 (immunoglobulin superfamily containing leucine-rich repeat protein 2) and STRA6 [stimulated by retinoic acid (RA) receptor 6], apparently mediated by allele-specific binding of the transcription factor thyroid hormone receptor beta. We further show that the protective rs7173049-G allele correlates with increased tissue expression levels of ISLR2 and STRA6 and that both genes are significantly downregulated in tissues of PEX patients together with other key components of the STRA6 receptor-driven RA signaling pathway. siRNA-mediated downregulation of RA signaling induces upregulation of LOXL1 and PEX-associated matrix genes in PEX-relevant cell types. These data indicate that dysregulation of STRA6 and impaired retinoid metabolism are involved in the pathophysiology of PEX syndrome and that the variant rs7173049-G, which represents the first common variant at the broad LOXL1 locus without allele effect reversal, mediates a protective effect through upregulation of STRA6 in ocular tissues.

The discovery and use of genetic markers associated with carotenoid levels can help to exploit the genetic potential of maize for provitamin A accumulation more effectively. Provitamin A carotenoids are classes of carotenoids that are precursors of vitamin A, an essential micronutrient in humans. Vitamin A deficiency is a global public health problem affecting millions of people, especially in developing countries. Maize is one of the most important staple crops targeted for provitamin A biofortification to help alleviate vitamin A deficiency in developing countries. A genome-wide association study (GWAS) of maize endosperm carotenoids was conducted using a panel of 130 diverse yellow maize tropical inbred lines genotyped with Genotyping by Sequencing (GBS) SNP markers. Numerous significant association signals co-localizing with the known carotenoid biosynthesis genes crtRB1, lcyE and ZEP1 were identified. The GWAS confirmed previously reported large effects of the two major carotenoid biosynthesis genes lcyE and crtRB1. In addition, significant novel associations were detected for several transcription factors (e.g., RING zinc finger domain and HLH DNA-binding domain super family proteins) that may be involved in regulation of carotenoid biosynthesis in maize. When the GWAS was re-conducted by including the major effects of lcyE and crtRB1 genes as covariates, a SNP in a gene coding for an auxin response factor 20 transcription factor was identified which displayed an association with β-carotene and provitamin A levels. Our study provides a foundation for design and implementation of genomics-assisted selection strategies for provitamin A maize breeding in tropical regions, and advances efforts toward identification of additional genes (and allelic variants) involved in the regulation of carotenoid biosynthesis in plants.

SUMMARY Maternally skewed transmission of traits has been associated with genomic imprinting and oocyte-derived mRNA. We report canine congenital eye malformations, caused by an amino acid deletion (K12del) near the N terminus of retinol-binding protein (RBP4). The disease is only expressed when both dam and offspring are deletion homozygotes. RBP carries vitamin A (retinol) from hepatic stores to peripheral tissues, including the placenta and developing eye, where it is required to synthesize retinoic acid. Gestational vitamin A deficiency is a known risk factor for ocular birth defects. The K12del mutation disrupts RBP folding in vivo, decreasing its secretion from hepatocytes to serum. The maternal penetrance effect arises from an impairment in the sequential transfer of retinol across the placenta, via RBP encoded by maternal and fetal genomes. Our results demonstrate a mode of recessive maternal inheritance, with a physiological basis, and they extend previous observations on dominant-negative RBP4 alleles in humans., In Brief Maternal inheritance distinctive from imprinting and oocyte-derived mRNA mechanisms has been regarded as a rare exception unique to humans. Kaukonen et al. describe a canine model with a recessive maternally transmitted RBP4 defect, suggesting that this mechanism is more common in developmental defects.

Micronutrient deficiency is a widespread phenomenon, most prevalent in developing countries. Being causally linked to the occurrence of a range of diseases, it affects billions of people worldwide. Enhancing the content of micronutrients in crop products through biotechnology is a promising technique to fight micronutrient malnutrition worldwide. Micronutrient fortification of food products has been implemented in a number of Western countries, but remains inaccessible for poor rural populations in a major part of the developing world. Moreover, evidence of the negative impacts of this practice on human health, at least for some vitamins, is accumulating. Biofortification of crop plants-the enhancement of vitamins and minerals through plant biotechnology-is a promising alternative or complement in the battle against micronutrient deficiencies. Owing to a growing knowledge about vitamin metabolism, as well as mineral uptake and reallocation in plants, it is today possible to enhance micronutrient levels in crop plants, offering a sustainable solution to populations with a suboptimal micronutrient intake.

Beta-carotene 15,15'-monooxygenase 1 knockout (Bcmo1 (-/-)) mice accumulate beta-carotene (BC) similarly to humans, whereas wild-type (Bcmo1 (+/+)) mice efficiently cleave BC. Bcmo1 (-/-) mice are therefore suitable to investigate BC-induced alterations in gene expression in lung, assessed by microarray analysis. Bcmo1 (-/-) mice receiving control diet had increased expression of inflammatory genes as compared to BC-supplemented Bcmo1 (-/-) mice and Bcmo1 (+/+) mice that received either control or BC-supplemented diets. Differential gene expression in Bcmo1 (-/-) mice was confirmed by real-time quantitative PCR. Histochemical analysis indeed showed an increase in inflammatory cells in lungs of control Bcmo1 (-/-) mice. Supported by metabolite and gene-expression data, we hypothesize that the increased inflammatory response is due to an altered BC metabolism, resulting in an increased vitamin A requirement in Bcmo1 (-/-) mice. This suggests that effects of BC may depend on inter-individual variations in BC-metabolizing enzymes, such as the frequently occurring human polymorphisms in BCMO1.

Background: Anemia is a major nutrition related problem in China. In addition to iron deficiency this may be due to deficiencies of other micronutrients. Objective: To describe the micronutrient status of anemic and non-anemic pregnant women in China. Subjects and Methods: 734 clinically normal pregnant women in the third trimester aged 20-35, were randomly recruited from the population of pregnant women regularly receiving pregnant examination in community medical centers. Serum concentrations of vitamins A, B-12 and C, iron and zinc status parameters, and vitamin B-2 in urine were determined. Subjects were categorized according to the presence or absence of anemia and compared according to micronutrient status. Results: Serum concentrations of iron and micronutrients were significantly lower in anemic women than non-anemic women: serum iron 909 mu g/L versus 1109 mu g/L, ferritin 13.8 mu g/L versus 19.6 mu g/L, vitamin C 308.9 mu g/L versus 388.1 mu g/dL, and retinol 50.0 mu g/dL versus 59.3 mu g/dL. Zinc concentrations were also lower in anemic women. Subnormal serum iron (

In rural China, many pregnant women in their third trimester suffer from anemia (48%) and iron deficiency (ID; 42%), often with coexisting deficiencies of retinol and riboflavin. We investigated the effect of retinol and riboflavin supplementation in addition to iron plus folic acid on anemia and subjective well-being in pregnant women. The study was a 2-mo, double-blind, randomized trial. Subjects (n = 366) with anemia [hemoglobin (Hb) 105 g/L] were randomly assigned to 4 groups, all receiving 60 mg/d iron and 400 µg/d folic acid. The iron+folic acid (IF) group (n = 93) served as reference, the iron+folic acid+retinol group (IFA) (n = 91) was treated with 2000 µg retinol, the iron+folic acid+riboflavin group (IFB) (n = 91) with 1.0 mg riboflavin, and the iron+folic acid+retinol+riboflavin group (IFAB) (n = 91) with retinol and riboflavin. After the 2-mo intervention, the Hb concentration increased in all 4 groups (P

Although retinol-binding protein (RBP)-4 concentrations are elevated in animal models of obesity and insulin resistance (IR), the link between RBP4 and IR in humans is less clear. There are few published data on RBP4 levels in overweight children, and most previous studies did not control for vitamin A (VA) status and/or subclinical inflammation.The objective of the study was to measure serum RBP4, serum retinol (SR), the RBP4-to-SR molar ratio, and dietary VA intakes in normal-weight and overweight children and investigate the relationship of these variables to IR, subclinical inflammation, and the metabolic syndrome in this age group.This was a cross-sectional study.The study was conducted in Northern Switzerland.Patients included 6- to 14-yr-old normal-weight, overweight, and obese children (n = 79).Body mass index, body fat percentage, waist-to-hip ratio, dietary VA intakes, serum RBP4, and SR were determined. IR was assessed using fasting insulin and the quantitative insulin sensitivity check index, and components of the metabolic syndrome and indices of subclinical inflammation were measured.Only 3% of children had low VA status. Independent of age, VA intakes, and C-reactive protein, body mass index, body fat percentage, and waist-to-hip ratio were significant predictors of RBP4, SR, and RBP4/SR. Independent of adiposity, RBP4 and RBP4/SR were significantly correlated with serum triglycerides, and RBP4/SR was correlated with fasting insulin. The RBP4-to-SR ratio more strongly correlated with components of the metabolic syndrome than serum RBP4.Independent of subclinical inflammation and vitamin A intakes, serum RBP4 and the RBP4-to-SR ratio are correlated with obesity, central obesity, and components of the metabolic syndrome in prepubertal and early pubertal children.

Background: Anemia is a major nutrition related problem in China. In addition to iron deficiency this may be due to deficiencies of other micronutrients. Objective: To describe the micronutrient status of anemic and non-anemic pregnant women in China. Subjects and Methods: 734 clinically normal pregnant women in the third trimester aged 20-35, were randomly recruited from the population of pregnant women regularly receiving pregnant examination in community medical centers. Serum concentrations of vitamins A, B-12 and C, iron and zinc status parameters, and vitamin B-2 in urine were determined. Subjects were categorized according to the presence or absence of anemia and compared according to micronutrient status. Results: Serum concentrations of iron and micronutrients were significantly lower in anemic women than non-anemic women: serum iron 909 mu g/L versus 1109 mu g/L, ferritin 13.8 mu g/L versus 19.6 mu g/L, vitamin C 308.9 mu g/L versus 388.1 mu g/dL, and retinol 50.0 mu g/dL versus 59.3 mu g/dL. Zinc concentrations were also lower in anemic women. Subnormal serum iron (

Objective: To review and summarize the dietary determinants of the metabolic syndrome, subclinical inflammation and dyslipidemia in overweight children. Design: Review of the current literature, focusing on pediatric studies. Participants: Normal weight, overweight, or obese children and adolescents. Results: There is a growing literature on the metabolic effects of excess body fat during childhood. However, few pediatric studies have examined the dietary determinants of obesity-related metabolic disturbances. From the available data, it appears that dietary factors are not only important environmental determinants of adiposity, but also may affect components of the metabolic syndrome and modulate the actions of adipokines. Dietary total fat and saturated fat are associated with insulin resistance and high blood pressure, as well as obesity-related inflammation. In contrast to studies in adults, resistin and adiponectin do not appear to be closely linked to insulin resistance or dyslipidemia in childhood. However, circulating leptin and retinol-binding protein (RBP) 4 correlate well with obesity, central obesity and the metabolic syndrome in children. Intakes of antioxidant vitamins tend to be low in obese children and may be predictors of subclinical inflammation. Higher fructose intake from sweets and sweetened drinks in overweight children has been linked to decreased low-density lipoprotein (LDL) particle size. Conclusions: Dietary interventions aimed at reducing intakes of total fat, saturated fat and free fructose, whereas increasing antioxidant vitamin intake may be beneficial in overweight children. More research on the relationships between dietary factors and the metabolic changes of pediatric obesity may help to identify the dietary changes to reduce health risks.

Objective: To describe the household intakes of retinol and carotenoids and social economic factors determining their intakes. Subjects: Data on a total of 1001 households (771 in rural areas and 230 in urban areas) were used in the analyses. Interviewed person was household food preparer. Results: Mean (s.d.) intake of carotenoids was 4178 (3154) mu g/capita/day in rural and 4208 (3408) mu g/capita/day in urban areas and intake of retinol was 101 (275) mu g/capita/day in rural and 201 (470) mu g/capita/day in urban areas. Multivariate analyses show that the subjects in households with four or more members consume about 700 mu g carotenoids less compared to households with less than three members. Households with a higher expenditure (fourth quartile) consumed about 100 mg retinol/day more than those with a lower expenditure (first quartile). Conclusion: Carotenoids from plant food sources is the main source of vitamin A intake of the population and its main determinants are household expenditure and size of household. Food fortification and dietary diversification with special emphasis on promotion of consumption of animal foods should be key strategies for overcoming vitamin A deficiency in Vietnam.

Gamma radiation is used to sterilize diets for specific pathogen-free (SPF) animals. Because a gamma-irradiated diet was linked to leukoencephalomyelopathy in SPF cats, we investigated the effects of 'typical' (28.9-34.3 kGy) and 'high-end' (38.4-48.7 kGy) doses of gamma irradiation and of pasteurization (at 107 degrees C for 15 min) on the amounts of fat; protein; carbohydrate (and taurine in cat diet); vitamins A, E, B, B-1, B-2, and B-12; and peroxide in commercially available dry cat, dog, and rodent diets. The only treatment-related changes occurred with vitamin A and peroxide. The typical and high-end doses of gamma irradiation reduced the vitamin A level of the cat diet to 42% and 30% of the untreated value, respectively-levels below recommended allowances for growth and reproduction. Only the higher irradiation dose reduced vitamin A in the rodent diet, and neither dose altered the canine diet. Pasteurization reduced the vitamin A content of the cat diet to 50% of its original level, which was within the recommended level for this species. Irradiation increased the peroxide content of all 3 animal diets: by approximately 11-fold with the typical dose and by 14- to 25-fold with the high-end dose. Therefore gamma irradiation can have profound, selective effects on the vitamin A and peroxide contents of dry diets, and caution is advised when feeding such diets long-term and exclusively to SPF animals, particularly cats. Furthermore, pasteurization (with its fewer deleterious effects) may represent an alternative method of decontaminating diets for rodents, dogs, and cats. peer-reviewed

In rural China, many pregnant women in their third trimester suffer from anemia (48%) and iron deficiency (ID; 42%), often with coexisting deficiencies of retinol and riboflavin. We investigated the effect of retinol and riboflavin supplementation in addition to iron plus folic acid on anemia and subjective well-being in pregnant women. The study was a 2-mo, double-blind, randomized trial. Subjects (n = 366) with anemia [hemoglobin (Hb) 105 g/L] were randomly assigned to 4 groups, all receiving 60 mg/d iron and 400 µg/d folic acid. The iron+folic acid (IF) group (n = 93) served as reference, the iron+folic acid+retinol group (IFA) (n = 91) was treated with 2000 µg retinol, the iron+folic acid+riboflavin group (IFB) (n = 91) with 1.0 mg riboflavin, and the iron+folic acid+retinol+riboflavin group (IFAB) (n = 91) with retinol and riboflavin. After the 2-mo intervention, the Hb concentration increased in all 4 groups (P

Anemia is a serious public health problem in Indian school children. Since 2003, simple health intervention programs such as antihelminthic treatment and vitamin A supplementation have been implemented in primary schools in the Bangalore region, Karnataka, India. This study examines the prevalence of anemia in school children who are beneficiaries of this program. Cross-sectional survey. Bangalore district, South India. A total of 2030 boys and girls, aged 5–15 years, attending schools in the Bangalore district. School-based, twice yearly intervention: deworming (albendazole 400 mg, single oral dose) and vitamin A supplementation (200 000 IU, single oral dose). Anemia prevalence based on measure of blood hemoglobin (Hb). Mean age and blood Hb concentration of all children were 9.5±2.6 years and 12.6±1.1 g/dl (range 5.6–16.7), respectively. The overall anemia prevalence in this group was 13.6%. Anemia prevalence was lower in boys than girls (12.0%; n=1037 vs 15.3%; n=993 respectively, P

The contribution of various factors to malnutrition, particularly stunting, may differ among areas and communities. This cross-sectional study aimed to estimate the level of malnutrition and identify factors associated with the high level of stunting in breast-fed infants aged 5-11 mo living in Dodota-Sire District, Ethiopia. Infants (n = 305) and their mothers were examined physically, and anthropometric and demographic data were collected. The content of zinc, calcium and copper in breast milk was measured, and data collected on the type, frequency of consumption, and time of introduction of supplementary feeding. Overall, 36% were stunted, 41% underweight and 13% wasted. The highest prevalence of malnutrition was seen in infants aged 9-11 mo. Among mothers, 27% had chronic energy deficiency (body mass index, 3 times/d, consuming > 600 mL/d or consuming cow's milk in addition to cereals and/or legumes had markedly higher length-for-age Z-scores than their peers fed less frequently, consuming less food or not consuming cow's milk [differences: 0.39, 95% confidence interval (Cl): 0.04-0.74; 0.17, 95% Cl: 0.02-0.32; 0.40, 95% Cl: 0.07-0.72, respectively]. Infants of mothers with low concentrations of zinc in their breast milk were more stunted. In conclusion, the quality and quantity of foods consumed by infants is insufficient to prevent stunting. Thus it is necessary to increase the,nutrient supply to infants by increasing intake and nutrient concentration of breast milk and of supplementary foods they consume, and by providing supplements to infants Where appropriate.

Background: Micronutrient supplementation has been extensively explored as a strategy to improve health and reduce risk of chronic diseases. Fat-soluble vitamins like A and E with their antioxidant properties and mechanistic interactions with lipoproteins, have potentially a key impact on lipid metabolism and lipidemia., Objective: The impact of micronutrients on lipid metabolism requires further investigation including characterization of plasma lipidome following supplementation and any cause-effect on circulating lipids., Design: In this study, we elucidate the effect and associations of a multi-micronutrient intervention in Brazilian children and teens with lipoprotein alterations and lipid metabolism., Results: Our analysis suggests a combination of short and long-term impact of supplementation on lipid metabolism, potentially mediated primarily by alpha-tocopherol (vitamin E) and retinol (vitamin A). Among the lipid classes, levels of phospholipids, lysophospholipids, and cholesterol esters were impacted the most along with differential incorporation of stearic, palmitic, oleic and arachidonic acids. Integrated analysis with proteomic data suggested potential links to supplementation-mediated alterations in protein levels of phospholipases and pyruvate dehydrogenase kinase 1 (PDK1)., Conclusions: Associations between the observed differences in lipidemia, total triglyceride, and VLDL-cholesterol levels suggest that micronutrients may play a role in reducing these risk factors for cardiovascular disease in children. This would require further investigation. (C) 2019 The Author(s). Published by Elsevier Ltd.

Background: Biofortification of staple crops is a cost effective and sustainable approach that can help combat vitamin A and other micronutrient deficiencies in developing countries. PCR -based DNA markers distinguishing alleles of three key genes of maize endosperm carotenoid biosynthesis (PSY1, lcyE and crtRB1) have been developed to facilitate maize provitamin A biofortification via marker assisted selection. Previous studies of these functional DNA markers revealed inconsistent effects. The germplasm previously employed for discovering and validating these functional markers was mainly of temperate origin containing low frequencies of the favourable allele of the most significant polymorphism, crtRB1-5'TE. Here, we investigate the vitamin A biofortification potential of these DNA markers in a germplasm panel of diverse tropical yellow maize inbred lines, with mixed genetic backgrounds of temperate and tropical germplasm to identify the most effective diagnostic markers for vitamin A biofortification. Results: The functional DNA markers crtRB1-5'TE and crtRB1-3'TE were consistently and strongly associated with provitamin A content across the tropical maize inbred lines tested. The alleles detected by these two functional markers were in high linkage disequilibrium (R-2 = 0.75) and occurred in relatively high frequency (18%). Genotypes combining the favourable alleles at the two loci (N = 20) displayed a 3.22 fold average increase in beta-carotene content compared to those genotypes lacking the favourable alleles (N = 106). The PSY1 markers were monomorphic across all of the inbred lines. The functional DNA markers for lcyE were associated with lutein, and with the ratio of carotenoids in the alpha and beta branches, but not with provitamin A levels. However, the combined effects of the two genes were stronger than their individual effects on all carotenoids. Conclusions: Tropical maize inbred lines harbouring the favourable alleles of the crtRB1-5'TE and 3'TE functional markers produce higher levels of provitamin A. Such maize lines can be used as donor parents to speed up the development of provitamin A biofortified tropical maize varieties adapted to growing conditions and consumer preferences, providing a route towards mitigation of vitamin A malnutrition in Sub-Saharan Africa.