A mutant insulin receptor gene lacking almost the entire kinase domain has been identified in an individual with type A insulin resistance and acanthosis nigricans.
With regard to keratin 6 mRNA, and the protein expression of keratin 6/16, KI-67, and proliferating cell nuclear antigen, the AN lesion showed moderate hyperproliferation.
We have used DGGE to screen for mutations in the insulin receptor gene in a family in which four of five daughters were affected by type A insulin resistance in association with acanthosis nigricans and hyperandrogenism.
We report here the identification of a mutation in the transmembrane region of FGFR3, common to three unrelated patients with classical Crouzon syndrome and acanthosis nigricans, a dermatological condition associated with thickening and abnormal pigmentation of the skin.
Therefore, any molecular model of the origin of acanthosis nigricans secondary to FGFR3 mutations must account for the association of diverse mutations and these cutaneous effects.
For our patients, clinical features are most helpful in differentiating NIDDM-Y from IDDM and include ethnic background, age and gender at diagnosis (approximately 80% of First Nation patients from northern Manitoba are adolescent females), presence of obesity and acanthosis nigricans, lack of symptoms or weight loss, and strong family history of NIDDM.
Affected individuals show an increased preponderance of insulin resistance, diabetes mellitus, dyslipidemia and acanthosis nigricans.The genetic basis of FPLD is unknown.
A novel skeletal dysplasia with developmental delay and acanthosis nigricans is caused by a Lys650Met mutation in the fibroblast growth factor receptor 3 gene.