In other words, it is at present unknown whether it is your genetic body clock itself, or living out of sync with it - for instance, forcing yourself to get up early for work if you are a lark - which affects your breast cancer risk.
"We also found some evidence for a causal effect of increased sleep duration and sleep fragmentation on breast cancer, assessed using objective measurements of sleep obtained from movement monitors worn by around 85,000 UK Biobank participants".
Researchers also looked at results from nearly 229,000 women signed up to an worldwide genetic study carried out by the Breast Cancer Association Consortium.
Richmond's team also analyzed genetic variants linked to whether someone is a morning or night personin more than 220,000 women to find out if these could help provide a causal link to breast cancer. However, experts warn more research is needed and the existing findings can not be applied more widely.
The study did not prove a cause-and-effect relationship between sleeping patterns and breast cancer risk. Researchers then mapped the genetic variations between the earlier risers and the night owls and compared it with that to the risk of developing cancer.
"The statistical method used in this study, called Mendelian randomization, does not always allow causality to be inferred", said Dipender Gill, clinical research training fellow at Imperial College London. The Breast Cancer Walk, which centered at the Manhattanville College Campus and directed its way up to SUNY Purchase, totaled five kilometers. "Another limitation is that sleep timing preference (chronotype) is self-reported, and the investigation did not specifically recruit individuals with different sleep patterns, such as night-shift workers", Burgess wrote in the comments of the study.
The findings have been published on researchers' website bioRxiv but have not yet gone through scientific peer review.
Mariam Hamad Al Nuaimi, General Manager of Qatar Cancer society said: "We truly value our partnership with Careem Qatar and the efforts set towards reaching out to their passengers to raise the awareness of the dangers of Breast Cancer".
Night owls shouldn't be anxious by the findings, said Richmond.
The study was presented Tuesday at the U.K.'s National Cancer Research Institute (NCRI) annual cancer conference, in Glasgow, Scotland.
Those that were found to have the genes of a morning person had a lower chance of getting breast cancer.
"These are interesting findings that provide further evidence of how our body clock and our natural sleep preference is implicated in the onset of breast cancer".