I spoke recently to Meg Wolitzer by phone.

It was 10am, New York time, and she was in her apartment, on the Upper East Side, talking quietly because her husband and two grown sons were still in bed. In the background, her dog was padding around the apartment, a place she described as full of books and dog toys and her sons' bikes. It was an appropriately homely setting for one of America's most interesting novelists, a writer who looks as if she is a typical mother-next-door, but whose fiction is barbed with political insights and the sort of psychological acuity that make for fascinating and sometimes uncomfortable reading.

Wolitzer was something of a prodigy when she first appeared on the literary scene. She wrote her first novel, Sleepwalking, while she was at the Ivy League's Brown University, and was 23 when it was published. From then on, her path as a writer was set, a financially precarious career shared with her husband Richard Panek, who writes popular science books. As she recalled, when their children were young, the only holidays they could afford were those paid for by magazines for whom they'd write satirical travel pieces.

While Wolitzer has established a reputation as a critically well-received novelist of modern, feminist ideas, she has still to reach the first rank of fame which many believe she deserves. Described variously as the female Jonathan Franzen or Jeffrey Eugenides, she has in the past railed against the lack of respect shown to women writers, whose work she believes is under-rated and under-reviewed compared to that of their male peers.

In earlier novels - most famously The Wife, The Ten-Year Nap and The Uncoupling - Wolitzer has addressed one of the most politically and emotionally fraught of all worlds, that of marriage, home and kids. In these, and in her own life story, one can already detect the seeds that have inspired her latest novel. The Interestings is an absorbingly long read that runs in parallel with Wolitzer's own life, starting in the 1970s, when she and her fictional characters first went to summer camp, and ending in the present day, by which stage she and her lively cast of six are well into their 50s.

The novel is dedicated to Wolitzer's parents, for sending her to the camp that made such an impact on her, and to a friend she met there with whom she is still close. In the novel, the camp that acts as the dramatic crucible is an eccentric compound of tepees in Massachusetts, run by an ageing couple devoted to the arts and those who show "talent". Youngsters go there to dance, draw, write, sing and perform, and for some, such as Wolitzer's heroine Julie, the experience is quite literally life-changing.

A 15-year-old whose father has just died, who lives with her mother and big sister in a dull New York suburb, Julie is adopted by a gang of decidedly cool kids, and will never be the same again. Renaming herself Jules from that day, she sheds the limitations of her upbringing and imagination, and pictures a bright future as a comic actress, since everyone tells her what a wit she is. Led by Ash and her brooding brother Goodman, the offspring of wealthy, sophisticated New Yorkers, this posse includes buxom dancer Cathy, the beautiful Jonah, whose mother is a famous folk singer, and an exceedingly talented cartoonist, Ethan, who looks like a nerd, and has "eczema running along his forearms like a lit fuse".

Ethan is the character around whom the plot revolves. As the self-styled group of Interestings revel in their own abilities, they innocently echo the elitism they will later encounter in the world at large. Over the years, however, only one of them will truly fulfil their early promise. As Ethan goes on to international acclaim and phenomenal wealth as a cartoonist of animated films, in the process marrying Ash, who is by now a theatre director dedicated to worthy feminist plays, the others revolve in their orbit, their lives looking increasingly woebegone and lacklustre.

It is Jules in whom jealousy bites deepest. Wolitzer's depiction of this young woman's bitterness at her ordinary life is painfully real. Realising her acting ambitions were misplaced, Jules instead becomes a counsellor, married to dependable but depressive Dennis, a man whose good nature and sense of perspective show up the pretensions and moral inadequacies of the original group, were she only able to see it. A shocking incident, in which Goodman is involved, creates ripples that run through the rest of their lives, an ethically charged situation handled by Wolitzer with a clever sense of timing, restraint and drama.

A baggy but charming book, which wears its learning and philosophy lightly, The Interestings is a compelling and powerful depiction of loss in many shapes: hope, youth, ambition, expectation and desire. Disappointment is the backbone of the book, but so too blindness to where happiness or contentment lie. Written with a compassionate but coruscating eye, it has moments of grand self-indulgence, as if nostalgia has managed briefly to get the upper hand. Contained within such a sweeping narrative, these passages are not only forgivable, but add to the powerful, affecting texture, whose keynote is poignancy. This is a meandering, unrestrained novel, reminiscent of a roman fleuve in its scope and tone, and carrying the reader effortlessly on, as if it were a river in spate.

Meg Wolitzer is at the Edinburgh International Book Festival on August 13, 10.15am