Genesis "Gennie" Walker is a fictional character from the British television soap opera Emmerdale, played by Sian Reese-Williams. She made her first appearance during the episode broadcast on 1 April 2008. Reese-Williams announced her departure from the show on 11 May 2013, and she made her last appearance on 26 July 2013.

Her storylines have focused on getting to know her family, the Dingles, including her birth father Shadrach Dingle (Andy Devine), developing unrequited feelings for Paddy Kirk (Dominic Brunt) and Bob Hope (Tony Audenshaw), her relationship with Jamie Hope (Alex Carter), her relationship and subsequent marriage to Nikhil Sharma (Rik Makarem), and being murdered by Cameron Murray (Dominic Power) after being involved in a car accident with him and Debbie Dingle (Charley Webb).

Gennie Walker was created while Kathleen Beedles was the series producer. By the time Gennie's first episode was broadcast on 1 April 2008, Anita Turner had taken over from Beedles. Theatre actress Sian Reese-Williams was cast in the role and started filming in the week beginning 3 March 2008. Paula Lane, who was later cast as Ella Forster, also auditioned for the role. The character was described by Turner as "not your typical Dingle", adding that "we've got some exciting storylines planned" with Gennie in "for a real culture shock when she meets her biological family." In May 2008, Turner told Kris Green from Digital Spy that Gennie "could be brilliant and it's about her finding that inner Dingle". She added that Gennie has "really hidden depths – it's more about her future in Emmerdale, rather than her past."

Gennie is characterised as a "madcap" and "bubbly" member of the show's Dingle family. A writer from itv.com described her as being "keen" to fit in with her family, but is "easily-led and naïve" to their scheming ways. Gennie is portrayed as "unlucky in love" and writers portrayed her as unable to have a long-term relationship. They added that Gennie is "girlie and giggly and enjoys hanging out with her mates in the village." She likes bright clothes and rabbits, and has a fear of cellars and moths. Reese-Williams later revealed in 2024 that she struggled with Gennie's characterisation and revealed it had a negative effect on her own self-confidence. Reese-Williams stated that Gennie constantly being branded as "unlucky in love" and an "ugly duckling" affected her well-being even years after leaving the show.

Producers paired Gennie in a relationship with Nikhil Sharma (Rik Makarem) and writers developed a wedding storyline for them. Their wedding day becomes problematic when Brenda Walker (Lesley Dunlop) is diagnosed with a brain tumour. She refuses to attend Gennie's wedding because of her illness, which causes Gennie to question marrying Nikhil. Advance spoilers revealed that Gennie would attempt to convince Brenda to attend. A reporter from TV easy revealed that Gennie would try to flee her wedding over Brenda's absence. Nikhil then tries to convince Gennie to go through with the ceremony. Brenda then collapses and is rushed into hospital, further ruining their wedding day. The incident forces Brenda to agree to life saving brain surgery.

On 11 May 2013, it was announced via an itv.com report that Reese-Williams was leaving the role. She stated "I have absolutely adored my five years playing Gennie and being part of such an iconic show. My decision to leave has nothing to do with Emmerdale – it's such a special place and I will always cherish it – but I feel it's the right time for me to say goodbye and find new challenges." It was also revealed that Gennie would depart during the British summer months. Producers did not reveal details about Gennie's departure, urging viewers to keep watching. Five days later, Makarem's departure as Nikhil was announced with no details about his departure story given. On 25 July 2013, Gennie was killed off when Cameron Murray (Dominic Power) suffocated her following a car accident. Details of the murder were kept a secret to ensure viewers would be surprised. She made her final appearance on 26 July 2013.

Gennie is accidentally knocked off her motorbike by Ross Kirk (Samuel Anderson) while on her way to meet her biological father, Shadrach Dingle (Andy Devine). She recovers in the hospital and becomes friends with Ross and his cousin Paddy (Dominic Brunt) when they visit her in hospital. Paddy invites her to Eli Dingle's (Joseph Gilgun) 28th birthday party, and while she is there, Gennie meets Shadrach and realises that she has found her father and she later reluctantly talks to Shadrach. He tells how he started looking for her after his godson Daniel Thomas died of sudden infant death syndrome. Shadrach had planned to leave his wife for Gennie's mother, Shirley Pascoe, but she died in childbirth. Feeling unable to take her home, he gave her up for adoption.

Gennie soon grows close to her father and his family, although her half-sister Chas Dingle (Lucy Pargeter) is initially resentful of her presence and the attention she gets from Shadrach. Gennie tries to prove she is a true Dingle and finally does so when she steals a client from Eric Pollard (Chris Chittell), making money in the process. She also helps Eli and their cousin Sam (James Hooton) burn down Pollard's factory. After growing close to Eli, they share a kiss but he tells her that he is not attracted to her and she insists she isn't attracted to him. Soon, Gennie moves in with the Dingles, which upsets her adoptive mother, Brenda, who is concerned about Gennie not having a job and her change in character. Chas convinces Brenda that Gennie is working at the vets, and for a short time, she does work there. On her way to a call out, Gennie runs over and kills a sheep. She and Eli are arrested for stealing the vet's drugs, but are released when the locum vet, Josh, explains that she was taking the drugs to the farm. After this incident, her mother again tries to persuade her to come home, but Gennie refuses, saying she felt like she fitted in with the Dingles.