When DNA Is(n't) Enough

Send us Fan MailWhen beloved schoolteacher Genai Coleman was shot while reading her Bible in her car, detectives thought they had an open-and-shut case after finding a cigarette butt in the stolen vehicle that matched suspect Donald Smith’s DNA. However, the investigation hit a wall when Donald revealed he had an identical twin brother, Ronald, sharing his exact genetic code...In our second case this week, we discuss a 1987 gas station sexual assault in Woodbridge, Virginia that went cold for nearly four decades until genetic genealogy led detectives to identical twins Russell and Robert Marubbio. With standard testing unable to point to a single suspect, scientists turned to ultra-deep whole-genome sequencing to hunt for microscopic somatic mutations created during embryonic division.Sources (Genai Coleman): 1) https://abcnews.com/TheLaw/atlanta-twin-murder-case-echoes-fingerprint-origins/story?id=99095862) https://www.foxnews.com/us/dna-georgia-womans-murder-leads-wrong-twin-investigator-says-crime-opportunity3) https://www.oxygen.com/criminal-confessions/crime-news/ronald-smith-guns-down-teacher-genai-coleman-carjacking4) https://www.cbsnews.com/news/identical-dna-murder-has-georgia-police-seeing-double-which-twin-did-it/Sources: (Marubbio)1) https://www.theguardian.com/us-news/2025/sep/02/identical-twin-convicted-dna2) https://www.dcnewsnow.com/news/local-news/virginia/prince-william-county/identical-twin-convicted-in-rape-cold-case-after-slight-difference-in-dna-identified-in-prince-georges-county/3) https://www.forensicmag.com/3594-All-News/621193-DNA-Analysis-Leads-to-Individual-Twin-in-1987-Rape-Cold-Case/Support the show