Restoring T and B cell generation in X-linked severe combined immunodeficiency mice through hematopoietic stem cells adenine base editing.

Base editing of hematopoietic stem/progenitor cells (HSPCs) is an attractive strategy for treating immunohematologic diseases. However, the feasibility of using adenine-base-edited HSPCs for treating X-linked severe combined immunodeficiency (SCID-X1), the influence of dose-response relationships on immune cell generation, and the potential risks have not been demonstrated in vivo. Here, a humanized SCID-X1 mouse model was established, and 86.67% ± 2.52% (n = 3) of mouse hematopoietic stem cell (HSC) pathogenic mutations were corrected, with no single-guide-RNA (sgRNA)-dependent off-target effects detected. Analysis of peripheral blood over 16 weeks post-transplantation in mice with different immunodeficiency backgrounds revealed efficient immune cell generation following transplantation of different amounts of modified HSCs. Therefore, a large-scale infusion of gene-corrected HSCs within a safe range can achieve rapid, stable, and durable immune cell regeneration. Tissue-section staining further demonstrated the restoration of immune organ tissue structures, with no tumor formation in multiple organs. Collectively, these data suggest that base-edited HSCs are a potential therapeutic approach for SCID-X1 and that a threshold infusion dose of gene-corrected cells is required for immune cell regeneration. This study lays a theoretical foundation for the clinical application of base-edited HSCs in treating SCID-X1.

Novel compound heterozygous variants in ARL13B lead to Joubert syndrome.

Joubert syndrome (JBTS) is a systematic developmental disorder mainly characterized by a pathognomonic mid-hindbrain malformation. All known JBTS-associated genes encode proteins involved in the function of antenna-like cellular organelle, primary cilium, which plays essential roles in cellular signal transduction and development. Here, we identified four unreported variants in ARL13B in two patients with the classical features of JBTS. ARL13B is a member of the Ras GTPase family and functions in ciliogenesis and cilia-related signaling. The two missense variants in ARL13B harbored the substitutions of amino acids at evolutionarily conserved positions. Using model cell lines, we found that the accumulations of the missense variants in cilia were impaired and the variants showed attenuated functions in ciliogenesis or the trafficking of INPP5E. Overall, these findings expanded the ARL13B pathogenetic variant spectrum of JBTS.

The spectrum of phenylalanine hydroxylase variants and genotype-phenotype correlation in phenylketonuria patients in Gansu, China.

BACKGROUND: Phenylketonuria (PKU) is a common, congenital, autosomal recessive, metabolic disorder caused by Phenylalanine hydroxylase (PAH) variants. METHODS: 967 PKU patients from Gansu, China were genotyped by Sanger sequencing, multiplex ligation-dependent probe amplification, and whole exome sequencing. We analyzed the variants of PAH exons, their flanking sequences, and introns. RESULTS: The detection of deep intronic variants in PAH gene can significantly improve the genetic diagnostic rate of PKU. The distribution of PAH variants among PKU subtypes may be related to the unique genetic background in Gansu, China. CONCLUSION: The identification of PAH hotspot variants will aid the development of large-scale neonatal genetic screening for PKU. The five new PAH variants found in this study further expand the spectrum of PAH variants. Genotype-phenotype correlation analysis may help predict the prognosis of PKU patients and enable precise treatment regimens to be developed.

Novel Variants of HPS6 Cause Suspected Ocular Albinism: A Report of 2 Cases and the Profile of HPS6 Variants.

INTRODUCTION: Hermansky-Pudlak syndrome (HPS) is a rare autosomal-recessive disease characterized by ocular albinism (OA) or oculocutaneous albinism (OCA), platelet dysfunction, and other symptoms. This study aimed to analyze the molecular defect in two Chinese families with suspected OA, as well as to investigate the profile of HPS6 variants and their genotype-phenotype correlations. METHODS: Seven members from two families were recruited and underwent clinical ophthalmologic examinations. The genomic DNA was extracted from peripheral blood leukocytes. Whole-exome sequencing was performed on the proband of family JX. The single coding exon of HPS6 was directly Sanger sequenced based on PCR amplification in all available family members. An additional 46 probands from families or sporadic cases with the pathogenic variants of HPS6 reported in the literature were reviewed. RESULTS: We identified two different compound heterozygous truncating variants of HPS6 in probands with suspected OA from two independent families. The proband of family JX had c.1674dup and c.503-504del variants, and the other proband from family CZ had a nonsense variant of c.1114C>T and a frameshift variant of c.1556del. Among them, c.1674dup and c.1556del variants in HPS6 have not been reported previously. Therefore, our patients were diagnosed as HPS6 disease by molecular diagnostics. In the retrospective cohort of HPS6 patients, we delineated the profile of HPS6 variants and revealed a significant overlap between CpG islands and the variants of HPS6, suggesting a potential link between DNA methylation and HPS6 variants. We also observed a spatial aggregation of the variants in 3D structure of HPS6 protein, implying the possible functional significance of these structural regions. In addition, we did not find any significant genotype-phenotype correlation of HPS6, and neither did we observe a correlation between the truncation length of the HPS6 protein and the phenotype of HPS6 disease. CONCLUSION: Our research expands the spectrum of HPS6 variants, providing a comprehensive delineation of their profile and systematically investigating genotype-phenotype correlations in HPS6. These findings could offer potentially valuable clues for investigating the molecular mechanism underlying HPS6 pathogenesis, as well as aiding the clinical diagnosis of HPS6 patients and improving disease prognosis.

[Genetic analysis of eighteen patients from Gansu Province with Tetrahydrobiopterin deficiency].

OBJECTIVE: To explore the genetic basis of eighteen patients with Tetrahydrobiopterin deficiency (BH4D) from Gansu Province. METHODS: Eighteen patients diagnosed with BH4D at Gansu Provincial Maternal and Child Health Care Hospital from January 2018 to December 2021 were selected as the study subjects. Whole exome sequencing was carried out, and candidate variants were verified by Sanger sequencing. RESULTS: All of the thirty-six alleles of the eighteen patients were successfully determined by molecular genetic testing. Sixteen patients were found to harbor variants of the PTS gene, and two had harbored variants of the QDPR gene. Ten variants were detected in the PTS gene, with the most common ones being c.259C>T (34.38%) and c.286G>A (15.63%). Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the c.259C>T was classified as a pathogenic variant, whilst the c.286G>A, c.166G>A, c.200C>T, c.272A>G, c.402A>C, c.421G>T, c.84_291A>G and c.317C>T were classified as likely pathogenic variants. A novel c.289_290insCTT variant was classified as likely pathogenic (PM1+PM2_Supporting+PM3+PP3+PP4). The two variants (c.478C>T and c.665C>T) detected in the QDPR gene were both classified as variants of uncertain significance (PM1+PM2_Supporting+PP3+PP4). CONCLUSION: Genetic testing has clarified the pathogenic variants in these BH4D patients, which has enabled timely and accurate clinical intervention and treatment, and provided a reference for genetic counseling and reproductive guidance for their families.

[Disease spectrum and pathogenic genes of inherited metabolic disorder in Gansu Province of China]. / ç”˜è‚ƒåœ°åŒºé—ä¼ ä»£è°¢ç— ç–¾ç— è°±åŠè‡´ç— åŸºå› åˆ†æž.

OBJECTIVES: To investigate the disease spectrum and pathogenic genes of inherited metabolic disorder (IMD) among neonates in Gansu Province of China. METHODS: A retrospective analysis was conducted on the tandem mass spectrometry data of 286 682 neonates who received IMD screening in Gansu Provincial Maternal and Child Health Hospital from January 2018 to December 2021. A genetic analysis was conducted on the neonates with positive results in tandem mass spectrometry during primary screening and reexamination. RESULTS: A total of 23 types of IMD caused by 28 pathogenic genes were found in the 286 682 neonates, and the overall prevalence rate of IMD was 0.63 (1/1 593), among which phenylketonuria showed the highest prevalence rate of 0.32 (1/3 083), followed by methylmalonic acidemia (0.11, 1/8 959) and tetrahydrobiopterin deficiency (0.06, 1/15 927). In this study, 166 variants were identified in the 28 pathogenic genes, with 13 novel variants found in 9 genes. According to American College of Medical Genetics and Genomics guidelines, 5 novel variants were classified as pathogenic variants, 7 were classified as likely pathogenic variants, and 1 was classified as the variant of uncertain significance. CONCLUSIONS: This study enriches the database of pathogenic gene variants for IMD and provides basic data for establishing an accurate screening and diagnosis system for IMD in this region.

[A case of mental retardation caused by a frameshift variant of SYNGAP1 gene].

OBJECTIVE: To explore the genetic basis for a child with mental retardation. METHODS: Whole exome sequencing was carried out for the child. Candidate variant was screened based on his clinical features and verified by Sanger sequencing. RESULTS: The child was found to harbor a c.995_1002delAGACAAAA(p.Asp332AlafsTer84) frameshift variant in the SYNGAP1 gene. Bioinformatic analysis suggested it to be pathogenic. The same variant was not detected in either parent. CONCLUSION: The c.995_1002delAGACAAAA(p.Asp332AlafsTer84) frameshift variant of the SYNGAP1 gene probably underlay the mental retardation in this child. Above finding has expanded the spectrum of SYNGAP1 gene variants and provided a basis for the diagnosis and treatment for this child.

Molecular diagnose of a large hearing loss population from China by targeted genome sequencing.

Hereditary hearing loss is genetically heterogeneous, with diverse clinical manifestations. Here we performed targeted genome sequencing of 227 hearing loss related genes in 1027 patients with bilateral hearing loss and 520 healthy volunteers with normal hearing to comprehensively identify the molecular etiology of hereditary hearing loss in a large cohort from China. We obtained a diagnostic rate of 57.25% (588/1027) for the patients, while 4.67% (48/1027) of the patients were identified with uncertain diagnoses. Of the implicated 35 hearing loss genes, three common genes, including SLC26A4(278/588), GJB2(207/588), MT-RNR1(19/588), accounted for 85.54% (503/588) of the diagnosed cases, while 32 uncommon hearing loss genes, including MYO15A, MITF, OTOF, POU3F4, PTPN11, etc. accounted for the remaining diagnostic rate of 14.46% (85/588). Apart from Pendred syndrome, other eight types of syndromic hearing loss were also identified. Of the 64 uncertain significant variants and 244 pathogenic/likely pathogenic variants identified in the patients, 129 novel variants were also detected. Thus, the molecular etiology presented with high heterogeneity with the leading causes to be SLC26A4 and GJB2 genes in the Chinese hearing loss population. It's urgent to develop a database of the ethnicity-matched healthy population as well as to perform functional studies for further classification of uncertain significant variants.

[Genetic analysis of two Chinese families with maple syrup urine disease].

OBJECTIVE: To carry out genetic analysis for 3 children from two Chinese families affected with maple syrup urine disease (MSUD). METHODS: Target capture - next-generation sequencing and Sanger sequencing were used to detect pathogenic variants associated with MSUD. RESULTS: The proband from family 1 was found to harbor homozygous c.560G>T (p.Gly187Val) variant of the BCKDHB gene (NM_000056), whilst the two patients from family 2 were found to harbor compound heterozygous variants c.197-2A>G (splicing)/c.218delT (p.F74Sfs*4) of the BCKDHB gene. Among these, the c.560G>T and c.218delT variants were unreported previously. CONCLUSION: The new variants discovered in this study have expanded the mutational spectrum of the BCKDHB gene.

Disrupted intraflagellar transport due to IFT74 variants causes Joubert syndrome.

PURPOSE: Ciliopathies are a group of disorders caused by defects of the cilia. Joubert syndrome (JBTS) is a recessive and pleiotropic ciliopathy that causes cerebellar vermis hypoplasia and psychomotor delay. Although the intraflagellar transport (IFT) complex serves as a key module to maintain the ciliary structure and regulate ciliary signaling, the function of IFT in JBTS remains largely unknown. We aimed to explore the impact of IFT dysfunction in JBTS. METHODS: Exome sequencing was performed to screen for pathogenic variants in IFT genes in a JBTS cohort. Animal model and patient-derived fibroblasts were used to evaluate the pathogenic effects of the variants. RESULTS: We identified IFT74 as a JBTS-associated gene in three unrelated families. All the affected individuals carried truncated variants and shared one missense variant (p.Q179E) found only in East Asians. The expression of the human p.Q179E-IFT74 variant displayed compromised rescue effects in zebrafish ift74 morphants. Attenuated ciliogenesis; altered distribution of IFT proteins and ciliary membrane proteins, including ARL13B, INPP5E, and GPR161; and disrupted hedgehog signaling were observed in patient fibroblasts with IFT74 variants. CONCLUSION: IFT74 is identified as a JBTS-related gene. Cellular and biochemical mechanisms are also provided.

Mutation analysis of TCOF1 gene in Chinese Treacher Collins syndrome patients.

BACKGROUND: Treacher Collins syndrome (TCS) is a rare autosomal dominant or recessive disorder, that involves unique bilateral craniofacial malformations. The phenotypes of TCS are extremely diverse. Interventional surgery can improve hearing loss and facial deformity in TCS patients. METHOD: We recruited seven TCS families. Variant screening in probands was performed by targeted next-generation sequencing (NGS). The variants identified were confirmed by Sanger sequencing. The pathogenicity of all the mutations was evaluated using the guidelines of the American College of Medical Genetics and Genomics (ACMG) and InterVar software. RESULTS: Three frameshift variants, two nonsense variants, one missense variant, and one splicing variant of TCOF1 were identified in the seven TCS probands. Five variants including c.1393C > T, c.4111 + 5G>C, c.1142delC, c.2285_2286delCT, and c.1719delG had not been previously reported. Furthermore, we report the c.149A > G variant for the first time in a Chinese TCS patient. We provided prenatal diagnosis for family 4. Proband 7 chose interventional surgery. CONCLUSION: We identified five novel variants in TCOF1 in Chinese patients with TCS, which expands the mutation spectrum of TCOF1 in TCS. Bone conduction hearing rehabilitation can improve hearing for TCS patients and prenatal diagnosis can provide fertility guidance for TCS families.

[Study on newborn screening for Duchenne muscular dystrophy and diagnostic strategy].

OBJECTIVE: To establish a newborn screening system for Duchenne muscular dystrophy (DMD) through assessment of MM isoenzyme of creatine kinase (CK-MM) activity. METHODS: The CK-MM level was detected using dry blood spot filter paper from 10 252 male newborns. The results were grouped based on their gestational age, sampling time and intervals between the experiments. The threshold value for CK-MM necessitating genetic testing was determined. Next-generation sequencing (NGS) was carried out for those with a CK-MM value over the threshold, and the result was verified by multiplex ligation-dependent probe amplification (MLPA). RESULTS: Based on the result of non-parametric rank sum test, the median CK-MM concentration has increased with the gestational age, and was inversely correlated with the age of the newborns among unaffected specimens. CK-MM on dry blood spot filter paper can be stable for 14 days at 2-8℃. Statistical analysis of CK-MM value of the 10 252 neonates suggested that the threshold may be set as 700 ng/mL. Exonic deletions were found in 2 confirmed cases, whose CK-MM level was greater than 2000 ng/mL. CONCLUSION: Detection of CK-MM in dry blood spot filter paper has provided an effective method for newborn screening of DMD. This simple and inexpensive method can be used for large-scale screening, which is of great value to the early intervention and treatment of the disease.

[Wiedemann-Steiner syndrome due to novel nonsense variant of KMT2A gene in a case].

OBJECTIVE: To explore the genetic basis for a child with unexplained global developmental delay (GDD), seizure, and facial deformity. METHODS: Whole exome sequencing (WES) was carried out for the patient. Candidate variants were verified by Sanger sequencing of the patient and his parents. RESULTS: WES revealed that the patient has carried a previously unreported de novo heterozygous nonsense c.4906C>T (p.Arg1636Ter) variant of the KMT2A gene, Based on the American College of Medical Genetics and Genomics standards and guidelines, the c.4906C>T variant of KMT2A gene was predicted to be pathogenic (PVS1+ PS2+ PM2+PP3). CONCLUSION: The heterozygous nonsense c.4906C>T (p.Arg1636Ter) variant of the KMT2A gene probably underlay the disease in the child. Above finding has enriched the spectrum of pathogenic variants of the KMT2A gene.

Identification of two novel pathogenic variants of PIBF1 by whole exome sequencing in a 2-year-old boy with Joubert syndrome.

BACKGROUND: Joubert syndrome (OMIM 213300) is an autosomal recessive disorder with gene heterogeneity. Causal genes and their variants have been identified by sequencing or other technologies for Joubert syndrome subtypes. CASE PRESENTATION: A two-year-old boy was diagnosed with Joubert syndrome by global development delay and molar tooth sign of mid-brain. Whole exome sequencing was performed to detect the causative gene variants in this individual, and the candidate pathogenic variants were verified by Sanger sequencing. We identified two pathogenic variants (NM_006346.2: c.1147delC and c.1054A > G) of PIBF1 in this Joubert syndrome individual, which is consistent with the mode of autosomal recessive inheritance. CONCLUSION: In this study, we identified two novel pathogenic variants in PIBF1 in a Joubert syndrome individual using whole exome sequencing, thereby expanding the PIBF1 pathogenic variant spectrum of Joubert syndrome.

Maternal UPD of chromosome 7 in a patient with Silver-Russell syndrome and Pendred syndrome.

BACKGROUND: Silver-Russell syndrome (SRS) is a heterogeneous imprinting disorder featuring severe intrauterine and postnatal growth retardation and dysmorphic features. Pendred syndrome (PDS) is an autosomal recessive disorder caused by mutations in the SLC26A4 gene characterized by sensorineural hearing loss. METHODS: Karyotyping analysis was performed to investigate any chromosomal abnormalities. Whole-genome copy number variation and loss of heterozygosity were analyzed using an Affymetrix CytoScan 750 K Microarray. Variant screening was performed by targeted next-generation sequencing on all known deafness-causing genes. RESULTS: The proband was a patient with SRS caused by maternal uniparental disomy 7. The PDS of the proband was caused by homozygous variant c.919-2A > G of SLC26A4; both mutated alleles were inherited from his mother. CONCLUSION: This is the first report of uniparental disomy 7 leading to SRS and Pendred syndrome. Patients with intrauterine growth retardation or those born small for gestational age and exhibiting postnatal growth failure should undergo molecular testing to reach a clinical diagnosis.

Mutation screening of crystallin genes in Chinese families with congenital cataracts.

Purpose: To identify mutations in crystallin genes in Chinese families with congenital cataracts. Methods: Forty-two unrelated families with non-syndromic congenital cataracts were enrolled in this study. The coding exons and adjacent intronic regions of crystallin genes, including CRYAA, CRYAB, CRYBA1, CRYBA4, CRYBB1, CRYBB2, CRYBB3, CRYGC, CRYGD and CRYGS, were analyzed with Sanger sequencing. Novel variants were further evaluated in 112 ethnically matched controls. To confirm the novel mutations, short tandem repeat (STR) haplotypes were constructed to check the cosegregation with congenital cataract. The pathogenic potential of the novel mutations were assessed using bioinformatics tools, including Sorting Intolerant From Tolerant v5.1.1 (SIFT), Polymorphism Phenotyping v2 (PolyPhen-2), and Human Splicing Finder. The pathogenicity of all the mutations was evaluated according to the guidelines of the American College of Medical Genetics (ACMG) and InterVar software. Results: Seven previously reported mutations in crystallin genes identified in ten unrelated families were associated with the congenital nuclear cataracts. Four novel mutations in crystallin genes, including c.35G>T (p.R12L) in CRYAA, c.463C>A (p.Q155K) in CRYBB2, IVS1 c.10-1G>A in CRYGC, and c.346delT (p.F116Sfsx29) in CRYGD, were identified in four unrelated families with congenital cataracts. These mutations cosegregated with all affected individuals in each family were not observed in the unaffected family members or in the 112 unrelated controls. All four novel mutations were categorized as disease "likely pathogenic" except IVS1 c.10-1G>A in CRYGC "pathogenic" using InterVar software in accordance with the ACMG standard. Mutations in crystallin genes were responsible for 33.33% of the Chinese families with congenital cataracts in this cohort. Conclusions: In this study, we identified four novel mutations in crystallin genes in Chinese families with congenital cataracts. The results expand the mutational spectrum of crystallin genes, which may be helpful for the molecular diagnosis of congenital cataracts in the era of precision medicine.

A multiplex droplet digital PCR assay for non-invasive prenatal testing of fetal aneuploidies.

Higher multiplexing in droplet digital PCR (ddPCR) can simplify the detection process of ddPCR-based non-invasive prenatal testing (NIPT) and improve its reliability, making it a practical approach in clinical practice. However, a high level of multiplex ddPCR-based NIPT has rarely been reported. In this study, we developed a multiplex ddPCR assay using universal locked nucleic acid (LNA) probes to reliably identify fetal aneuploidies. We first performed statistical analysis based on the Poisson distribution to evaluate the required number of target DNA molecules and the total number of droplets for a ddPCR assay. Next, we designed two sets of primers and probes to quantify cfDNA from chromosomes 21 and 18 and then determined the disease status of a sample. Finally, we evaluated our multiplex ddPCR assay with 60 clinical plasma samples. All of the 60 clinical samples were correctly identified. The accessibility and cost-effectiveness of our multiplex ddPCR-based NIPT make it a competitive prenatal testing method in clinical use.

Novel mutations in HSF4 cause congenital cataracts in Chinese families.

BACKGROUND: Congenital cataract, a kind of cataract presenting at birth or during early childhood, is a leading cause of childhood blindness. To date, more than 30 genes on different chromosomes are known to cause this disorder. This study aimed to identify the HSF4 mutations in a cohort from Chinese families affected with congenital cataracts. METHODS: Forty-two unrelated non-syndromic congenital cataract families and 112 ethnically matched controls from southeast China were recruited from the southeast of China. We employed Sanger sequencing method to discover the variants. To confirm the novel mutations, STR haplotypes were constructed to check the co-segregation with congenital cataract. The pathogenic potential of the novel mutations were assessed using bioinformatics tools including SIFT, Polyphen2, and Human Splicing Finder. The pathogenicity of all the mutations was evaluated by the guidelines of American College of Medical Genetics and InterVar software. RESULTS: No previously reported HSF4 mutations were found in all the congenital cataract families. Five novel HSF4 mutations including c.187 T > C (p.Phe63Leu), c.218G > T (p.Arg73Leu), c.233A > G (p.Tyr78Cys), IVS5 c.233-1G > A and c.314G > C (p.Ser105Thr) were identified in five unrelated families with congenital cataracts, respectively. These mutations co-segregated with all affected individuals in each family were not observed in the unaffected family members or in 112 unrelated controls. All five mutations were categorized to be the disease "pathogenic" according to ACMG guidelines and using InterVar software. Mutations in the HSF4 were responsible for 11.90% Chinese families with congenital cataracts in our cohort. CONCLUSIONS: In the study, we identified five novel HSF4 mutations in Chinese families with congenital cataracts. Our results expand the spectrum of HSF4 mutations causing congenital cataracts, which may be helpful for the molecular diagnosis of congenital cataracts in the era of precision medicine.

Folic acid supplementation, preconception body mass index, and preterm delivery: findings from the preconception cohort data in a Chinese rural population.

BACKGROUND: Folic acid (FA) supplementation before and during the first trimester can reduce the risk of occurrence of preterm delivery (PTD). Preconception body mass index (BMI) is also associated with PTD. This study aimed to investigate the combined effect of FA supplements and preconception BMI on the risk of PTD. METHODS: The data of a cohort from 2010-2011 that was obtained through a preconception care service in China was used (including 172,206 women). A multivariable regression model was used to investigate the association between maternal preconception conditions and the risk of PTD. The interaction of preconception BMI and FA supplementation was measured by a logistic regression model. RESULTS: Taking FA supplements in the preconception period or in the first trimester reduced the risk of PTD (odds ratio [OR] = 0.58 and OR = 0.61, respectively). Women with an abnormal BMI had an increased risk of PTD (OR = 1.09, OR = 1.10, and OR = 1.17 for underweight, overweight, and obese, respectively). Preconception BMI showed an interaction with the protective effect of FA supplementation for PTD. With regard to the interaction of FA supplementation, the adjusted odds ratio (aOR) was 0.57 (95% CI: 0.51, 0.64) in underweight women, 0.85 (95% CI: 0.73, 0.98) in overweight women, and 0.77 (95% CI, 0.65, 0.91) in obese women. Preconception BMI also showed an interaction with the time of FA supplementation. Women with a normal BMI who began to take FA supplements in the preconception period had the lowest risk of PTD (aORs: 0.58 vs. 0.65 beginning in the first trimester). The aORs at preconception and the first trimester in the underweight group were 0.56 vs. 0.60. The aORs at preconception and the first trimester were 0.94 vs. 0.65 and 1.15 vs. 0.60 in the overweight and obesity groups, respectively. CONCLUSIONS: In our study, FA supplements reduced the risk of PTD, while abnormal BMI raised the risk of PTD, although higher BMI categories did not have this higher risk once adjusted analysis was conducted. The protective effect of FA supplementation for PTD was reduced in women with overweight or obesity. To get better protection of FA supplementation, women with normal BMI or underweight should begin to use in preconception, while women with overweight or obesity should begin to use after conception.