Clinical Information (ข้อมูลทางคลินิก):
Non-Invasive Prenatal Testing (NIPT) is a non-invasive test for pregnant women which estimates the risk of a fetus having chromosomal abnormalities. The non-invasive prenatal testing (NIPT) is an advanced screening test using next -generation sequencing technology that is carried out on a small maternal blood sample. During pregnancy, the placenta leaks cell-free DNA (deoxyribonucleic acid) which circulates in the maternal bloodstream. As a result, a maternal blood sample contains a mixture of fetal-placental and maternal circulating cell-free DNA. The non-invasive prenatal testing (NIPT) directly measures the amount of this cell-free DNA and can detect chromosomal abnormalities. People usually have 23 pair of chromosomes or 46 chromosomes (23 from mother and 23 from father). There are many different types of chromosome abnormalities such as numerical abnormalities (trisomies, monosomies) structural abnormalities (microdeletions, translocations) and mosaicism. Some fetal chromosome abnormalities may relate to advanced maternal age, but may occur as a result of errors in cell division, inheritance of abnormalities or by multiple factors.
Details of each test item as follows:
1. Screening for Trisomy 13, trisomy18 and trisomy 21
• Trisomy 13 (Patau syndrome): A chromosomal disorder that causes serious problems with the brain and heart as well as extra fingers and toes, cleft palate and lip, and other defects. Most infants with trisomy 13 die within the first year of life.
• Trisomy 18 (Edwards syndrome): A chromosomal disorder that causes severe intellectual disability and serious physical problems such as a small head, heart defects, and deafness. Most of those affected with trisomy 18 die before birth or within the first month of life.
• Trisomy 21 (Down syndrome): A chromosomal disorder that causes abnormal features of the face and body, medical problems such as heart defects, and intellectual disability. Many children with Down syndrome live to adulthood.
2. Screening for Sex chromosome aneuploidy
• Monosomy X or XO (Turner syndrome): A chromosomal disorder that affects development in female, common feature is short stature, extra folds of skin on the neck, early loss of ovarian function, infertility. Developmental delay, learning disabilities and heart defects may present.
• XXX (Triple X syndrome): Signs and symptoms can vary from no noticeable effect to delayed development of speech and language skill, learning disabilities and hypotonia. Normal sexual development and fertility are typical.
• XXY (Klinefelter syndrome): Signs and symptoms often subtle, primary features are infertility and small testis. Intelligence is usually normal but reading difficulties and speech problems may present.
• XYY (Jacob’s syndrome): Signs and symptoms are few, may taller than average and increased risk of learning and speech problems, no problem with fertility.
3. Screening for other chromosome aneuploidy includes chromosomes 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 19, 20 and 22.
4. Sex determination (optional)
Clinical Reference (เอกสารอ้างอิง):
1. Witters G, Van Robays J, Willekes C, Coumans A, Peeters H, Gyselaers W, Fryns JP. Trisomy 13, 18, 21, Triploidy and Turner syndrome: the 5T's. Look at the hands. Facts Views Vis Obgyn. 2011;3(1):15-21. PMID: 24753843; PMCID: PMC3991414.
2. Swaiman, K. F., Ashwal, S., Ferriero, D. M., Schor, N. F., Finkel, R. S., Gropman, A. L., Pearl, P. L., & Shevell, M. I. (2017). Swaiman's Pediatric Neurology: Principles and Practice: Sixth Edition. Elsevier Inc.
3. Sepulveda, W., Wimalasundera, R.C., Taylor, M.J.O., Blunt, S., Be, C. and De La fuente, S. (2003), Prenatal ultrasound findings in complete trisomy 9. Ultrasound Obstet Gynecol, 22: 479-483. https://doi.org/10.1002/uog.233
4. Trevisan V, Meroni A, Leoni C, Sirchia F, Politano D, Fiandrino G, Giorgio V, Rigante D, Limongelli D, Perri L, et al. Trisomy 22 Mosaicism from Prenatal to Postnatal Findings: A Case Series and Systematic Review of the Literature. Genes. 2024; 15(3):346. https://doi.org/10.3390/genes15030346
5. Screening for Fetal Chromosomal Abnormalities ACOG Practice Bulletin, Number 226
6. Dungan JS, Klugman S, Darilek S, Malinowski J, Akkari YMN, Monaghan KG, Erwin A, Best RG; ACMG Board of Directors. Noninvasive prenatal screening (NIPS) for fetal chromosome abnormalities in a general-risk population: An evidence-based clinical guideline of the American College of Medical Genetics and Genomics (ACMG). Genet Med. 2023 Aug;25(8):100874. doi: 10.1016/j.gim.2023.100874. Epub 2023 Jun 27. Erratum for: Genet Med. 2023 Feb;25(2):100336. doi: 10.1016/j.gim.2022.11.004. PMID: 37378664.
7. Cereda A, Carey JC. The trisomy 18 syndrome. Orphanet J Rare Dis. 2012 Oct 23;7:81. doi: 10.1186/1750-1172-7-81. PMID: 23088440; PMCID: PMC3520824.
8. Shankar Kikkeri N, Nagalli S. Turner Syndrome. [Updated 2023 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK554621/
9. Bardsley MZ, Kowal K, Levy C, Gosek A, Ayari N, Tartaglia N, Lahlou N, Winder B, Grimes S, Ross JL. 47,XYY syndrome: clinical phenotype and timing of ascertainment. J Pediatr. 2013 Oct;163(4):1085-94. doi: 10.1016/j.jpeds.2013.05.037. Epub 2013 Jun 27. PMID: 23810129; PMCID: PMC4097881.
10. Wigby K, D'Epagnier C, Howell S, Reicks A, Wilson R, Cordeiro L, Tartaglia N. Expanding the phenotype of Triple X syndrome: A comparison of prenatal versus postnatal diagnosis. Am J Med Genet A. 2016 Nov;170(11):2870-2881. doi: 10.1002/ajmg.a.37688. Epub 2016 Sep 19. PMID: 27644018; PMCID: PMC6501572.
11. Mbuyi-Musanzayi S, Lumaka A, Kasole TL, Ilunga EK, Asani BY, Tshilobo PL, Muenze PK, Reychler H, Katombe FT, Devriendt K. Wolf-Hirschhorn Syndrome: Clinical and Genetic Data from a First Case Diagnosed in Central Africa. J Pediatr Genet. 2017 Sep;6(3):186-190. doi: 10.1055/s-0037-1599194. Epub 2017 Mar 7. PMID: 28794913; PMCID: PMC5548528.
12. National Center for Biotechnology Information (US). Genes and Disease [Internet]. Bethesda (MD): National Center for Biotechnology Information (US); 1998-. Chromosome Map. Available from: https://www.ncbi.nlm.nih.gov/books/NBK22266/