Introduction: Knowing if the document that supports the informed consent (IC) granted by the patient who undergoes genetic laboratory tests is legible and understandable is important. Objective: To analyze the readability of IC documents for laboratory genetic tests (LGT) in Mexico. Methods: Readability of 10 free IC forms on the internet used for LGT was analyzed using the Legible.es program; the Flesh index, Fernández-Huerta version, and the INFLESZ scale were evaluated. The number of syllables, words, phrases, paragraphs and strange words, time to read the document and minimum years of education required to understand it were counted. Results: 60 % of the analyzed IC documents were found to have poor readability. On average, 3,290 syllables, 1,459 words, 124 sentences, 58 paragraphs and 52 strange words were counted. The time required for reading it was seven minutes and minimum level of education to understand it was six years. Conclusions: The analyzed IC forms for LGT have low readability rates and exceed the recommended number of words. We propose an IC model for LGT in Mexico that complies with appropriate readability indexes for a correct understanding of the document.