CRY1 and cytomegalovirus infection: And results showed that PER1 and CRY1 mRNA was significantly decreased in HCMV infection than in the controls (<i>P</i> < 0.0001; <i>P</i> < 0.0001).<h4>Conclusion</h4>PER1 and CRY1 mRNA was significantly decreased in PBMCs from HCMV infected VLBW infants, providing new ideas for studying potential effective therapeutic targets for HCMV infection in VLBW infants.