Early-onset colorectal cancer: A sporadic or inherited disease?

Table 2 Genetic background of early-onset colorectal cancer: Susceptibility genes and genetic/epigenetic variants

High risk susceptibility genes	Related hereditary syndrome
MLH1	Lynch
MSH2	Lynch
MSH6	Lynch
PMS2	Lynch
EpCAM	Lynch
MUTYH	MAP
BMPR1A	Juvenile polyposis
SMAD4	Juvenile polyposis
PTEN	Cowden
Genetic/Epigenetic variants	Related colorectal tumour
rs107956681	CRC < 50 yr
rs38028421	CRC < 50 yr
rs47795841	CRC < 50 yr
≥ 1 CCND1 rare variants2	multiple adenomas or CRC < 50 yr
LINE-1 hypomethylation3	CRC < 50 yr
DNA repetitive elements hypermethylation4	CRC < 60 yr
10q22-q23del5	Two synchronous CRC at 49 yr of age

¹Colorectal cancer (CRC) genetic susceptibility single nucleotide polymorphisms with a P-value< 0.05[92];

²P-value = 0.04 and OR = 2.0[94];

³Comparison of long interspersed nuclear element 1 (LINE-1) hypomethylation status between early-onset CRC and other groups of CRC: P-value< 0.0001[95];

⁴DNA repetitive elements hypermethylation in a cohort of early-onset CRC patients compared to healthy controls: LINE-1 (OR = 2.34, P-value < 0.001), Sat2 (OR = 1.72, P-value < 0.001) and Alu repeats (OR = 1.83, P-value = 0.02)[96];

⁵The 10q22-q23 deletion in the patient involves the BMPR1A gene[97]. MAP: MUTYH associated polyposis.