Familial acromegaly without features of multiple endocrine neoplasie type 1 (MEN 1) is an exceptional clinical entity. We report in this article three cases of acromegaly due to pituitary macroadenomas without any other endocrinopathy in a family. A 31-year-old woman (subject A) and her 34-year-old sister (subject B) with elevated basal rolactin (PRL) levels, elevated growth hormone (GH) levels during the oral glucose tolerance test (OGTT) and a pituitary adenoma in Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) were diagnosed as acromegaly. Subject A was treated only with radiotherapy and Lysuride. Subject B underwent transsphenoidal microsurgical extirpation 15 years ago. 11 years later her 24-year-old son (subject C) also presented with typical signs of acromegaly, elevated basal PRL level and elevated GH levels during OGTT. A pituitary macroadenoma was identified by MRI and he also underwent transsphenoidal adenomectomy. Pathology reports confirmed the diagnosis of GH-secreting pituitary adenoma in subject B and C. Immunocytochemistry revealed that tumours of subject B (> 20% of tumour cells) and C (> 50% of tumour cells) were positive for GH. Tumours of subject B (> 10% of tumour cells) and C (> 50% of tumour cells) also exhibited immunoreactivity for PRL. On investigation of histocompatibility antigens, it was observed that the subject A, B, and C shared the same haplotypes [HLA A24(9), HLA B13(6), HLA 1335, HLA DQ7(3), HLA DR13(6)] and so it is very possible that investigation of HLA antigens in patients with pituitary turnout, contributes to better identification of its familial nature and frequency. Here we describe an acromegaly family and the distributions of HLA antigens.