Question: In American Gothic painting who where the people modeled after?
About the article "American Gothic", section "Abstract".

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Wood's best known work is his 1930 painting "American Gothic", which is also one of the most famous paintings in American art, and one of the few images to reach the status of universally recognised cultural icon, comparable to Leonardo da Vinci's "Mona Lisa" and Edvard Munch's "The Scream".
It was first exhibited in 1930 at the Art Institute of Chicago, where it is still located.
It was given a $300 prize and made news stories country-wide, bringing Wood immediate recognition.
Since then, it has been borrowed and satirised endlessly for advertisements and cartoons.
Art critics who had favorable opinions about the painting, such as Gertrude Stein and Christopher Morley, assumed the painting was meant to be a satire of repression and narrow-mindedness of rural small-town life.
It was seen as part of the trend toward increasingly critical depictions of rural America, along the lines of Sherwood Anderson's "1919 Winesburg, Ohio", Sinclair Lewis' 1920 "Main Street", and Carl Van Vechten's "The Tattooed Countess" in literature.
Wood rejected this reading of it.
With the onset of the Great Depression, it came to be seen as a depiction of steadfast American pioneer spirit.
Another reading is that it is an ambiguous fusion of reverence and parody.
Wood's inspiration came from Eldon, southern Iowa, where a cottage designed in the Gothic Revival style with an upper window in the shape of a medieval pointed arch, provided the background and also the painting's title.
Wood decided to paint the house along with "the kind of people I fancied should live in that house."
The painting shows a farmer standing beside his spinster daughter, figures modeled by the artist's dentist and sister, Nan (1900–1990).
Wood's sister insisted that the painting depicts the farmer's daughter and not wife, disliking suggestions it was the farmer's wife, since that would mean that she looks older than Wood's sister preferred to think of herself.
The dentist, Dr. Byron McKeeby (1867–1950) was from Cedar Rapids, Iowa.
The woman is dressed in a dark print apron mimicking 19th century Americana with a cameo brooch and a tightly-knotted tie, and the couple are in the traditional roles of men and women, the man's pitchfork symbolizing hard labor.
The compositional severity and detailed technique derive from Northern Renaissance paintings, which Grant had looked at during three visits to Europe; after this he became increasingly aware of the Midwest's own legacy, which also informs the work.
It is a key image of Regionalism.
Wood was hired in 1940, along with eight other prominent American artists, to document and interpret dramatic scenes and characters during the production of the film "The Long Voyage Home", a cinematic adaptation of Eugene O'Neill's plays. 
American Gothic is a painting by Grant Wood in the collection of the Art Institute of Chicago.
Wood's inspiration came from what is now known as the American Gothic House, and his decision to paint the house along with "the kind of people I fancied should live in that house."
The painting shows a farmer standing beside his spinster daughter.
The figures were modeled by the artist's sister and their dentist.
The woman is dressed in a colonial print apron evoking 19th-century Americana, and the couple are in the traditional roles of men and women, the man's pitchfork symbolizing hard labor, and the flowers over the woman's right shoulder suggesting domesticity.
It is one of the most familiar images in 20th-century American art, and has been widely parodied in American popular culture.
"American Gothic" is a painting by Grant Wood from 1930.
Wood's inspiration came from a cottage designed in the Carpenter Gothic style with a distinctive upper window and a decision to paint the house along with "the kind of people I fancied should live in that house."
In August 1930, Grant Wood, an American painter with European training, was driven around Eldon, Iowa by a young painter from Eldon, John Sharp, looking for inspiration.
Wood noticed the Dibble House, a small white house built in the Carpenter Gothic architectural style.
Sharp's brother suggested in 1973 that it was on this drive that Wood first sketched the house on the back of an envelope.
Wood's earliest biographer, Darrell Garwood, noted that Wood "thought it a form of borrowed pretentiousness, a structural absurdity, to put a Gothic-style window in such a flimsy frame house."
At the time, Wood classified it as one of the "cardboardy frame houses on Iowa farms" and considered it "very paintable".
After obtaining permission from the Jones family, the house's owners, Wood made a sketch the next day in oil on paperboard from the house's front yard.
This sketch displayed a steeper roof and a longer window with a more pronounced ogive than on the actual house, features which eventually adorned the final work.
Wood decided to paint the house along with "the kind of people I fancied should live in that house."
He recruited his sister Nan (1899–1990) to model the woman, dressing her in a colonial print apron mimicking 19th-century Americana.
The man is modeled on Wood's dentist, Dr. Byron McKeeby (1867–1950) from Cedar Rapids, Iowa.
The three-pronged hay fork is echoed in the stitching of the man's overalls, the Gothic window of the house, and the structure of the man's face.
However, Wood did not add figures to his sketch until he returned to his studio in Cedar Rapids.
He would not return to Eldon again before his death in 1942, although he did request a photograph of the home to complete his painting. 
The Depression-era understanding of the painting as a depiction of an authentically American scene prompted the first well-known parody, a 1942 photo by Gordon Parks of cleaning woman Ella Watson, shot in Washington, D.C."American Gothic" is one of the few paintings to achieve iconic cultural status, along with Leonardo da Vinci's "Mona Lisa" and Edvard Munch's "The Scream".
It is thus one of the most reproduced – and parodied – images ever made.
Many artists have replaced the two people with other known couples and replaced the house with well-known houses.
References and parodies of the image have been numerous for generations, appearing regularly in such media as postcards, magazines, animated cartoons, advertisements, comic books, album covers, television shows and other artists.
The opening credits of the 1965 television show "Green Acres" had the main couple in an American Gothic-style pose; cinematic posters of the films "For Richer or Poorer", "Son In Law", "American Gothic", and "Good Fences" parody the painting.
It is also a key motif in Anthony Weigh's play "2,000 Feet Away", which opens with a scene featuring the painting at the Art Institute.
The painting was also parodied in a classic commercial for "New Country Corn Flakes", a General Mills product.
A sculpture entitled "God Bless America" by sculptor John Seward Johnson II that features the "American Gothic" couple went on display in Chicago, Illinois, just south of the Tribune Tower on the Magnificent Mile of Michigan Avenue, in December 2008 but has been removed as of February 26, 2010.
The sculpture was displayed in Dubuque, Iowa at the Figge Art Museum and is now on the campus of Simpson College in Indianola, Iowa until at least December 31, 2013.
Postcards mimicking the couple with sitting US Presidents, Presidential nominees, and their spouses are popular commercial products.
Ohio State Buckeyes football games feature the painting on their scoreboard; within a few seconds of its display, the man's eyes bug out and his tongue wags.
A 1963 "Saturday Evening Post" cover featured the cast of "The Beverly Hillbillies" in a parody of American Gothic with "Irene Ryan" and "Buddy Ebsen" posing like the 2 people in the painting flanked by "Max Baer" and "Donna Douglas" at their sides.
David Ackles borrowed the title for his 1973 "American Gothic" album, as did The Smashing Pumpkins for their 2008 EP "American Gothic" and a 1995 television horror series created by Shaun Cassidy.
Elton John and RuPaul portray the couple on the video for a rerecording of "Don't Go Breaking My Heart" released in 1994.
Astrovamps parodied the painting on the cover of their album, "American Gothik".
The Ma and Pa couple at the beginning of the "Doctor Who" episode "Gridlock" are fashioned in the style of the couple in the painting.
The "American Gothic" couple have even been reinterpreted as Living Dead Dolls twice, in 2004 and 2009.
In the opening scene of "The Rocky Horror Picture Show", Richard O'Brien and Patricia Quinn appear as a farmer and his wife in parody of "American Gothic".
They are joined by a daughter dressed in the same fashion.
The painting is also seen on the wall in the castle during the song "Time Warp" as well as it is seen in the sequel "Shock Treatment"In the episode of "The Simpsons", "Bart Gets an Elephant", the Simpsons are revealed to evidently have the original "American Gothic" painting hanging on their living room wall.
Bart unwittingly scrubs it while cleaning the house, and rubs off all the paint.
Underneath, it reads "If you can read this, you scrubbed too hard.
Signed, Grant Wood.
"In the scene where Mulan's ancestors awaken Mushu in "Mulan", two of the ancestors appear as a parody of the farmer and his daughter, representing traditional values.
The painting and its process of creation was parodied in a "Saturday Night Live" episode, which aired November 10, 2012, with host Anne Hathaway as Nan Wood Graham, Jason Sudeikis as Dr. Byron McKeeby, Tarran Killam as Grant Wood, and Kenan Thompson as a tour guide at The Art Institute of Chicago.