Can polymorphisms in the fatty acid desaturase (FADS) gene cluster alter the effects of fish oil supplementation on plasma and erythrocyte fatty acid profiles? An exploratory study

Nutritional Status of Breastfeeding Mothers and Impact of Diet and Dietary Supplementation: A Narrative Review

Adequate nutrition during breastfeeding is crucial for ensuring the good health of mothers and babies. Despite the high energy and nutrient demands of breastfeeding, lactating women are often vulnerable from a nutritional perspective. The nutritional focus during breastfeeding tends to be on the newborn, often neglecting the mother's diet. Therefore, in the present narrative review, nutrient intakes were compared with the dietary reference values (DRVs) proposed by the European Food Safety Authority (EFSA) as well as by the World Health Organization/Food and Agriculture Organization (WHO/FAO). In the diets of lactating mothers, dietary inadequacies were observed in the intake of some vitamins, such as folic acid, vitamin B12, vitamin A, and vitamin D, and in the intake of certain minerals like calcium, iron, and iodine; polyunsaturated omega-3 fatty acid deficiencies, primarily in eicosapentaenoic acid and docosahexaenoic acid, were also observed. On the other hand, the debate on the necessity of supplementation during lactation continues; the need for nutritional supplementation during lactation depends on many factors, such us mothers' eating habits. There seems to be a positive association between nutritional supplementation of the lactating mother and the concentration of certain nutrients in human milk. The present narrative review provides an update on the nutritional status (fatty acids and micronutrients) of breastfeeding mothers and the impact of diet and dietary supplementation on human milk composition.

Effect of FADS1 rs174556 Genotype on Polyunsaturated Fatty Acid Status: A Systematic Review and Meta-Analysis

PUFA status is highly implicated in cognitive development and metabolic disorder-related diseases. Genetic variants of FADS genes encoding enzymes that catalyze the rate-limiting steps of PUFA biosynthesis appear to be associated with n-3 and n-6 PUFA contents. Therefore, we conducted the first systematic review and meta-analysis to explore the association of the A-allele carriers of the FADS1 rs174556 with PUFA status. The PRISMA guidelines were followed. The literature search was conducted up to November 2022 in PubMed, Web of Science, Embase, Cochrane Library, Airiti Library, and CINAHL. The Joanna Briggs Institute checklists were used to assess the methodological quality. The correlation with 95% CIs was determined by a random-effect meta-analysis. Eleven studies that met the inclusion criteria and acceptable quality were included in this systematic review. The data on PUFA contents were collected when they were mainly analyzed using blood samples and breast milk. Results of the meta-analysis on eight studies (one randomized controlled trial, one cohort study, and six cross-sectional studies) showed that the A-allele carriers of rs174556 were significantly negatively correlated with the concentrations of AA (P = 0.001), EPA (P = 0.004), and DHA (P = 0.025). However, ALA and LA were not associated with the A-allele carriers. To clarify the discrepancy, we further divided the studies into blood samples and breast milk subgroups. The subgroup analysis revealed that the A-allele carriers of rs174556 were significantly positively correlated with LA (P = 0.031) and negatively correlated with AA (P = 0.001), EPA (P = 0.036), and DHA (P < 0.001) in the blood sample group, but not in the breast milk group. The current meta-analysis proved that the A-allele carriers of the FADS1 rs174556 appeared to be highly associated with lower concentrations of AA, EPA, and DHA but higher LA in the blood samples. The study has been registered on the International Prospective Register of Systematic Reviews (PROSPERO:CRD42022363978). Adv Nutr 2023;x:xx-xx.

Metabolic Signatures Elucidate the Effect of Body Mass Index on Type 2 Diabetes

Obesity plays an important role in the development of insulin resistance and diabetes, but the molecular mechanism that links obesity and diabetes is still not completely understood. Here, we used 146 targeted metabolomic profiles from the German KORA FF4 cohort consisting of 1715 participants and associated them with obesity and type 2 diabetes. In the basic model, 83 and 51 metabolites were significantly associated with body mass index (BMI) and T2D, respectively. Those metabolites are branched-chain amino acids, acylcarnitines, lysophospholipids, or phosphatidylcholines. In the full model, 42 and 3 metabolites were significantly associated with BMI and T2D, respectively, and replicate findings in the previous studies. Sobel mediation testing suggests that the effect of BMI on T2D might be mediated via lipids such as sphingomyelin (SM) C16:1, SM C18:1 and diacylphosphatidylcholine (PC aa) C38:3. Moreover, mendelian randomization suggests a causal relationship that BMI causes the change of SM C16:1 and PC aa C38:3, and the change of SM C16:1, SM C18:1, and PC aa C38:3 contribute to T2D incident. Biological pathway analysis in combination with genetics and mice experiments indicate that downregulation of sphingolipid or upregulation of phosphatidylcholine metabolism is a causal factor in early-stage T2D pathophysiology. Our findings indicate that metabolites like SM C16:1, SM C18:1, and PC aa C38:3 mediate the effect of BMI on T2D and elucidate their role in obesity related T2D pathologies.

Personalized nutrition: A review of genotype-based nutritional supplementation

Nutritional disorders have become a major public health issue, requiring increased targeted approaches. Personalized nutrition adapted to individual needs has garnered dramatic attention as an effective way to improve nutritional balance and maintain health. With the rapidly evolving fields of genomics and nutrigenetics, accumulation of genetic variants has been indicated to alter the effects of nutritional supplementation, suggesting its indispensable role in the genotype-based personalized nutrition. Additionally, the metabolism of nutrients, such as lipids, especially omega-3 polyunsaturated fatty acids, glucose, vitamin A, folic acid, vitamin D, iron, and calcium could be effectively improved with related genetic variants. This review focuses on existing literatures linking critical genetic variants to the nutrient and the ways in which these variants influence the outcomes of certain nutritional supplementations. Although further studies are required in this direction, such evidence provides valuable insights for the guidance of appropriate interventions using genetic information, thus paving the way for the smooth transition of conventional generic approach to genotype-based personalized nutrition.

Association between FADS Gene Expression and Polyunsaturated Fatty Acids in Breast Milk

Polyunsaturated fatty acid (PUFA) in breast milk provides physiological benefits for offspring and is closely related to endogenous biosynthesis in lactating women. Few studies have addressed the association between fatty acid desaturase (FADS) gene expression patterns and fatty acids in breast milk. This research aimed to explore the differences in PUFA levels among breast milk groups with different levels of FADS gene expression and provide a scientific basis for precision nutrition strategies. A total of 50 healthy women 42–45 days postpartum were included in this study. A basic information questionnaire and breast milk samples were collected. Eight types of PUFA were detected, and RNA was extracted from breast milk. The transcription level of the FADS gene was detected using real-time quantitative PCR. Significant differences in the content of gamma-linolenic acid and eicosatrienoic acid (C20:3n6) were found in breast milk among FADS1 gene transcription groups (p = 0.009, p = 0.042, respectively). No significant differences in PUFA were found among the FADS2 and FADS3 gene expression groups. The results demonstrated that n-6 PUFA was associated with the mRNA expression levels of the FADS1 gene. They are of great significance in developing new methods and diets to optimize infant feeding using breast milk.

Translating n-3 polyunsaturated fatty acid status from whole blood to plasma and red blood cells during pregnancy: Translating n-3 status across blood fractions in pregnancy

Women with low n-3 (omega-3) status in pregnancy can reduce their risk of early preterm birth (<34 weeks' gestation) through n-3 long chain polyunsaturated fatty acid (LCPUFA) supplementation. As investigators measure fatty acid status in different blood fractions, equations are needed to compare results across studies. Similarly, derived cut-points for defining low and replete n-3 status are needed to assist clinical interpretation during early pregnancy. Our aims were to develop equations to convert the percentage of total n-3 fatty acids, EPA+DHA and DHA between whole blood, plasma and red blood cells (RBC), and to derive cut-points for defining low and replete total n-3 fatty acid status in plasma and RBC from those already established in whole blood. Using blood samples from 457 pregnant women in a multicentre randomised controlled trial, equations for these interconversions were developed using simple linear regression models. Measures of n-3 fatty acid status in whole blood and plasma were strongly related (R² > 0.85), while more moderate relationships were observed between measures in whole blood and RBC (R² 0.55 - 0.71), or plasma and RBC (R² 0.55 - 0.63). Using the conversion equations, established cut-points for low and replete n-3 status in whole blood (<4.2% and >4.9% of total fatty acids) converted to <3.7% and >4.3% of plasma total fatty acids, and to <7.3% and >8.1% of RBC total fatty acids. Agreement to define low and replete n-3 status was better between whole blood and plasma, rather than between whole blood and RBC. Our data also show that total n-3 fatty acids in plasma and serum are interchangeable. We conclude that either whole blood or plasma total n-3 fatty acids can be used to define low status in pregnancy and identify women who will most benefit from n-3 LCPUFA supplementation to reduce their risk of early birth. Further research is needed to determine the clinical utility of other fatty acid measures in various blood lipid fractions.

Associations Of Delta Fatty Acid Desaturase Gene Polymorphisms With Lipid Metabolism Disorders

Overweight, obesity, type 2 diabetes mellitus, metabolic syndrome, cardiovascular diseases, and non-alcoholic fatty liver disease are common chronic ailments associated with lipid metabolism disorders. One of the mechanisms of these disorders is related to the deficiency and/or change in the balance of essential fatty acids (FAs). At the same time, the provision of ω3 and ω6 polyunsaturated fatty acids (PUFAs) depends, besides sufficient dietary intake, on efficiency of their endogenous biosynthesis by desaturation and elongation processes regulated by FA elongases and FA desaturases. Desaturases are encoded by PUFA desaturase genes (FADSs): FADS1 and FADS2. Alteration of FA desaturase activity and single nucleotide polymorphisms (SNPs) in the FADS1 and FADS2 gene cluster are associated with lipid metabolism dysfunction and may affect the pathogenesis of lipid-related diseases. People of different ages, from different ethnic backgrounds and countries may exhibit varying degrees of response to dietary supplements of ω3 and ω6 PUFAs. The study of the relationship between lipid metabolism disorders and genetic factors controlling FA metabolism is an important research area since the health effects of alimentary ω3 and ω6 PUFAs can depend on genetic variants of the FADS genes. This review summarizes the literature data on the association of FADS gene polymorphisms with lipid metabolism disorders and their role in the development of chronic non-communicable pathologies associated with changes in lipid metabolism.

Omega-3 Fatty Acid Dietary Supplements Consumed During Pregnancy and Lactation and Child Neurodevelopment: A Systematic Review

BACKGROUND

Maternal nutrition during pregnancy and lactation has profound effects on the development and lifelong health of the child. Long-chain PUFAs are particularly important for myelination and the development of vision during the perinatal period.

OBJECTIVES

We conducted a systematic review to examine the relationship between supplementation with omega-3 fatty acids during pregnancy and/or lactation and neurodevelopment in children, to inform the Scientific Report of the 2020 Dietary Guidelines Advisory Committee.

METHODS

We identified articles on omega-3 fatty acid supplementation in pregnant and lactating women that included measures of neurodevelopment in their children (0-18 y) by searching PubMed, CENTRAL, Embase, and CINAHL Plus. After dual screening articles for inclusion, we qualitatively synthesized and graded the strength of evidence using pre-established criteria for assessing risk of bias, consistency, directness, precision, and generalizability.

RESULTS

We included 33 articles from 15 randomized controlled trials (RCTs) and 1 prospective cohort study. Of the 8 RCTs that delivered omega-3 fatty acid dietary supplements during pregnancy alone (200-2200 mg/d DHA and 0-1100 mg/d EPA for approximately 20 wk), 5 studies reported ≥1 finding that supplementation improved measures of cognitive development in the infant or child by 6%-11% (P < 0.05), but all 8 studies also reported ≥1 nonsignificant (P > 0.05) result. There was inconsistent or insufficient evidence for other outcomes (language, social-emotional, physical, motor, or visual development; academic performance; risks of attention deficit disorder, attention-deficit/hyperactivity disorder, autism spectrum disorder, anxiety, or depression) and for supplementation during lactation or both pregnancy and lactation. Populations with a lower socioeconomic status and adolescents were underrepresented and studies lacked racial and ethnic diversity.

CONCLUSIONS

Limited evidence suggests that omega-3 fatty acid supplementation during pregnancy may result in favorable cognitive development in the child. There was insufficient evidence to evaluate the effects of omega-3 fatty acid supplementation during pregnancy and/or lactation on other developmental outcomes.

The influence of fish consumption on serum n-3 polyunsaturated fatty acid (PUFA) concentrations in women of childbearing age: a randomised controlled trial (the iFish Study)

PURPOSE

Long-chain polyunsaturated fatty acids (LCPUFA) can be synthesised endogenously from linoleic acid (LA) and α-linolenic acid (ALA) in a pathway involving the fatty acid desaturase (FADS) genes. Endogenous synthesis is inefficient; therefore, dietary intake of preformed LCPUFA from their richest source of fish is preferred. This study investigated the effect of fish consumption on PUFA concentrations in women of childbearing age while stratifying by FADS genotype. The influence of fish consumption on lipid profile, and markers of inflammation and oxidative stress was also examined.

METHODS

Healthy women (n = 49) provided a buccal swab which was analysed for FADS2 genotype (rs3834458; T/deletion). Participants were stratified according to genotype and randomised to an intervention group to receive either no fish (n = 18), 1 portion (n = 14) or 2 portions (n = 17) (140 g per portion) of fish per week for a period of 8 weeks. Serum PUFA was analysed at baseline and post-intervention. Lipid profile, and markers of inflammation and oxidative stress were also analysed.

RESULTS

Participants consuming 2 portions of fish per week had significantly higher concentrations of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and total n-3 PUFA, and a lower n-6:n-3 ratio compared to those in the no fish or 1 portion per week group (all p < 0.05). Fish consumption did not have a significant effect on biomarkers of oxidative stress, inflammation and lipid profile in the current study.

CONCLUSION

Consumption of 2 portions of fish per week has beneficial effects on biological n-3 PUFA concentrations in women of childbearing age; however, no effects on oxidative stress, inflammation or lipid profile were observed. This trial was registered at www.clinicaltrials.gov (NCT03765580), registered December 2018.

Breastfeeding and the origins of health: Interdisciplinary perspectives and priorities

Breastfeeding and human milk (HM) are critically important to maternal, infant and population health. This paper summarizes the proceedings of a workshop that convened a multidisciplinary panel of researchers to identify key priorities and anticipated breakthroughs in breastfeeding and HM research, discuss perceived barriers and challenges to achieving these breakthroughs and propose a constructive action plan to maximize the impact of future research in this field. Priority research areas identified were as follows: (1) addressing low breastfeeding rates and inequities using mixed methods, community partnerships and implementation science approaches; (2) improving awareness of evidence-based benefits, challenges and complexities of breastfeeding and HM among health practitioners and the public; (3) identifying differential impacts of alternative modes of HM feeding including expressed/pumped milk, donor milk and shared milk; and (4) developing a mechanistic understanding of the health effects of breastfeeding and the contributors to HM composition and variability. Key barriers and challenges included (1) overcoming methodological limitations of epidemiological breastfeeding research and mechanistic HM research; (2) counteracting 'breastfeeding denialism' arising from negative personal breastfeeding experiences; (3) distinguishing and aligning research and advocacy efforts; and (4) managing real and perceived conflicts of interest. To advance research on breastfeeding and HM and maximize the reach and impact of this research, larger investments are needed, interdisciplinary collaboration is essential, and the scientific community must engage families and other stakeholders in research planning and knowledge translation.

Transcriptome-metabolome analysis of fatty acid of Bamei pork and Gansu Black pork in China

To study the difference in transcriptome level of fatty acid metabolism pathway in Bamei pork and the difference of pork quality caused by the difference. In this study, Bamei pigs breeding in Huzhu farm of QingHai province were selected as the test object, compared with Gansu Black pigs. Four indexes of nutmeg acid (DX1), palmitic acid (DX2), stearic acid (DX3) and linoleic acid (DX4) were set. The expression profiles of fat metabolism related genes between the two groups samples were analysed by GCMS metabolomics and transcriptomics, then coexpression network analysis were conducted to obtain phenotypic related genes. The results showed that the metabolic levels of DX3 and DX4 were significantly higher than those of other fatty acids. Among these differences, the ENSSSCG00000024681 (G1) and ENSSSCG00000036883 (G2) genes play important regulatory roles in fatty acid metabolism, and the upregulated expression of their gene obviously affects the level of fatty acid metabolism, thereby affecting the quality and taste of pork. In addition, we found that there was a good correlation between the same lines, and the genetic traits of the hybrid lines of Bamei pig and Black pig are more inclined to Bamei pig. In the independent fatty acid metabolism, "Mg²⁺"and flavin adenine dinucleotide are more active, which plays an important role in energy utilization. Therefore, we can be inferred that the metabolism of stearic acid and linoleic acid are important fatty acids for pork quality. It also further confirms that the research method of combined omics is of great significance for the study of species traits and gene functions.

Influence of fatty acid desaturase (FADS) genotype on maternal and child polyunsaturated fatty acids (PUFA) status and child health outcomes: a systematic review

CONTEXT

Polyunsaturated fatty acids (PUFA) are important during pregnancy for fetal development and child health outcomes. The fatty acid desaturase (FADS) genes also influence PUFA status, with the FADS genes controlling how much product (eg, arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid) is metabolized from the precursor molecules linoleic acid and α-linolenic acid.

OBJECTIVE

The current review discusses the influence of FADS genotype on PUFA status of pregnant women, breast milk, and children, and also how FADS may influence child health outcomes.

DATA SOURCES

The Ovid Medline, Scopus, Embase, Cochrane Library, CINAHL Plus, PubMed and Web of Science databases were searched from their inception to September 2018.

DATA EXTRACTION

Eligible studies reported FADS genotype and blood concentrations of PUFA during pregnancy, in childhood, breast milk concentrations of PUFA or child health outcomes.

DATA ANALYSIS

In pregnant and lactating women, minor allele carriers have higher concentrations of linoleic acid and α-linolenic acid, and lower concentrations of arachidonic acid, in blood and breast milk, respectively. In children, FADS genotype influences PUFA status in the same manner and may impact child outcomes such as cognition and allergies; however, the direction of effects for the evidence to date is not consistent.

CONCLUSION

Further studies are needed to further investigate associations between FADS and outcomes, as well as the diet-gene interaction.

Impact of erythrocyte long-chain omega-3 polyunsaturated fatty acid levels in early pregnancy on birth outcomes: findings from a Belgian cohort study

OBJECTIVE

To examine the association between maternal erythrocyte long-chain omega-3 PUFA (n-3 LCPUFA), measured in early pregnancy, and pregnancy and birth outcomes.

STUDY DESIGN

One hundred and eight healthy women with a singleton pregnancy were included. Erythrocyte fatty acids were analyzed using gas chromatography. Gestational length, birth anthropometric measures, and pregnancy-associated complications were collected from hospital medical records.

RESULTS

We observed significant positive associations between maternal docosahexaenoic acid (DHA) levels (p = 0.024) and omega-3 index values (p = 0.021) and gestational length in adjusted linear regression models. Each point in maternal DHA level was associated with 2.19 days longer gestational duration (β = 2.19; 95% CI 0.29-4.09). No consistent associations were found between n-3 PUFA levels and composite pregnancy outcome.

CONCLUSION

These findings suggest that the gestational length is positively affected by maternal n-3 LCPUFA status as soon as the early stages of pregnancy.

Biological Role of Unsaturated Fatty Acid Desaturases in Health and Disease

Polyunsaturated fatty acids (PUFAs) are considered one of the most important components of cells that influence normal development and function of many organisms, both eukaryotes and prokaryotes. Unsaturated fatty acid desaturases play a crucial role in the synthesis of PUFAs, inserting additional unsaturated bonds into the acyl chain. The level of expression and activity of different types of desaturases determines profiles of PUFAs. It is well recognized that qualitative and quantitative changes in the PUFA profile, resulting from alterations in the expression and activity of fatty acid desaturases, are associated with many pathological conditions. Understanding of underlying mechanisms of fatty acid desaturase activity and their functional modification will facilitate the development of novel therapeutic strategies in diseases associated with qualitative and quantitative disorders of PUFA.

Seafood, fatty acid biosynthesis genes, and multiple sclerosis susceptibility

BACKGROUND

The role of omega-3 fatty acid in multiple sclerosis (MS) susceptibility is unclear.

OBJECTIVE

To determine whether fish/seafood intake or genetic factors that regulate omega-3 fatty acids levels are associated with MS risk.

METHODS

We examined the association of fish and shrimp consumption and 13 tag single nucleotide polymorphisms (SNPs) in FADS1, FADS2, and ELOV2 with risk of MS in 1153 individuals from the MS Sunshine Study, a case-control study of incident MS or clinically isolated syndrome (CIS), recruited from Kaiser Permanente Southern California.

RESULTS

Consuming fish/seafood at least once a week or at least once a month with regular fish oil use was associated with 44% reduced odds of MS/CIS (adjusted OR = 0.56; 95% CI = 0.41-0.76; p = 0.0002) compared with consuming fish/seafood less than once a month and no fish oil supplementation. Two FADS2 SNPs (rs174611 and rs174618) were independently associated with a lower risk of MS (adjusted ORs = 0.74, 0.79, p = 0.0056, 0.0090, respectively). Association of FADS2 SNPs with MS risk was confirmed in an independent dataset.

CONCLUSION

These findings suggest that omega-3 fatty acid intake may be an important modifiable risk factor for MS. This is consistent with the other known health benefits of fish consumption and complementary genetic studies supporting a key role for omega-3 regulation.

FADS1 and FADS2 Polymorphisms Modulate Fatty Acid Metabolism and Dietary Impact on Health

Variants in the FADS gene cluster modify the activity of polyunsaturated fatty acid (PUFA) desaturation and the lipid composition in human blood and tissue. FADS variants have been associated with plasma lipid concentrations, risk of cardiovascular diseases, overweight, eczema, pregnancy outcomes, and cognitive function. Studies on variations in the FADS genecluster provided some of the first examples for marked gene-diet interactions in modulating complex phenotypes, such as eczema, asthma, and cognition. Genotype distribution differs markedly among ethnicities, apparently reflecting an evolutionary advantage of genotypes enabling active long-chain PUFA synthesis when the introduction of agriculture provided diets rich in linoleic acid but with little arachidonic and eicosapentaenoic acids. Discovering differential effects of PUFA supply that depend on variation of FADS genotypes could open new opportunities for developing precision nutrition strategies based either on an individual's genotype or on genotype distributions in specific populations.

Imbalance between Omega-6 and Omega-3 Polyunsaturated Fatty Acids in Early Pregnancy Is Predictive of Postpartum Depression in a Belgian Cohort

While studies revealed that the omega-3 polyunsaturated fatty acids (n-3 PUFA) and their mediators would be able to regulate several biological processes involved into the development of postpartum depression (PPD), evidence from observational studies remains mixed. The aim of the present study was to investigate the association between maternal erythrocyte n-3 PUFA, measured in early pregnancy, and the risk of PPD. A Belgian cohort of 72 healthy women was screened. Erythrocyte fatty acids were analysed using gas chromatography. PPD was assessed using the Bromley Postnatal Depression Scale by phone interview one year after delivery. We observed a significant negative association between docosahexaenoic acid (DHA) levels and the risk of postpartum depression in the adjusted model (p = 0.034). Higher n-6/n-3 and arachidonic acid (AA)/eicosapentaenoic acid (EPA) ratios were significantly associated with an increased odds of PPD (p = 0.013 and p = 0.043, respectively). Women with an omega-3 index <5% had a 5-fold increased risk of depressive episode than did those with an omega-3 index ≥5% (OR 5.22 (95% CI 1.24–21.88)). A low n-3 PUFA status, alone and combined with high n-6 PUFA status, in early pregnancy was associated with a greater risk of PPD. Management of maternal n-3 PUFA deficiency can be a simple, safe and cost-effective strategy for the prevention of this major public health issue.

The Effect of an Infant Formula Supplemented with AA and DHA on Fatty Acid Levels of Infants with Different FADS Genotypes: The COGNIS Study

Polymorphisms in the fatty acid desaturase (FADS) genes influence the arachidonic (AA) and docosahexaenoic (DHA) acid concentrations (crucial in early life). Infants with specific genotypes may require different amounts of these fatty acids (FAs) to maintain an adequate status. The aim of this study was to determine the effect of an infant formula supplemented with AA and DHA on FAs of infants with different FADS genotypes. In total, 176 infants from the COGNIS study were randomly allocated to the Standard Formula (SF; n = 61) or the Experimental Formula (EF; n = 70) group, the latter supplemented with AA and DHA. Breastfed infants were added as a reference group (BF; n = 45). FAs and FADS polymorphisms were analyzed from cheek cells collected at 3 months of age. FADS minor allele carriership in formula fed infants, especially those supplemented, was associated with a declined desaturase activity and lower AA and DHA levels. Breastfed infants were not affected, possibly to the high content of AA and DHA in breast milk. The supplementation increased AA and DHA levels, but mostly in major allele carriers. In conclusion, infant FADS genotype could contribute to narrow the gap of AA and DHA concentrations between breastfed and formula fed infants.