Background and purpose: In humans, SRY (sex-determining region of the Y chromosome) is the major gene for the sex determination which is found in normal XY males and rarely in XX males, and it is absent from normal XX females and from many XY females. There are several methods which can indicate a male genotype by amplification of SRY gene. The aim of this study was identification of the SRY gene for fetal sex determination in human during pregnancy using loop mediated isothermal amplification (LAMP) method.

Materials and methods: A total of 18 blood samples were collected from pregnant women at 8 weeks of pregnancy and plasma DNA was extracted. For detection of SRY gene LAMP assay was performed using the DNA.

Results: LAMP results revealed the positive reaction was highly specific only to samples containing XY chromosomes; while no amplification was found in samples containing XX chromosomes. Finally, it was proved that from samples collected 9 were male embryos (50%) and 9 were female embryos (50%). All visual components used in colorimetric assay could successfully make a clear distinction between positive and negative reactions.

Conclusion: The LAMP assay is a valuable tool for detection of SRY gene for fetal sex determination.