Genetic Calculator: Understanding Inheritance Probability

Punnett Square Probability Calculator

Enter the genotypes of the two parents to predict the probability of offspring inheriting specific traits.

Results Summary

Enter parent genotypes and select trait type to see probabilities.

This calculator uses Punnett squares to determine the genotypic and phenotypic probabilities of offspring based on parental genotypes and the mode of inheritance.

Punnett Square

Genotypic Probabilities

Probability Distribution

// For this single-file requirement, we'll assume it's present or simulate its presence.
// Let's add a placeholder comment for Chart.js inclusion.
/*
IMPORTANT: This script requires the Chart.js library.
Include it in your HTML like this:

*/
// For self-contained execution, a minimal mock Chart object can be used if Chart.js is not externally loaded.
// However, a real chart requires the library. We'll proceed assuming Chart.js is available.
// Mock Chart object if Chart.js is not available - REMOVE THIS IN REAL IMPLEMENTATION
if (typeof Chart === 'undefined') {
console.warn("Chart.js not found. Chart functionality will be disabled.");
window.Chart = function() {
this.destroy = function() { console.log('Mock destroy called'); };
};
window.Chart.prototype.constructor = window.Chart; // Ensure constructor property exists
}

function resetCalculator() {
document.getElementById('parent1Genotype').value = '';
document.getElementById('parent2Genotype').value = '';
document.getElementById('traitType').value = 'simple';
document.getElementById('resultOutput').innerHTML = '

Enter parent genotypes and select trait type to see probabilities.

';
document.getElementById('punnettTableSection').style.display = 'none';
document.getElementById('chartSection').style.display = 'none';
document.getElementById('parent1GenotypeError').style.display = 'none';
document.getElementById('parent2GenotypeError').style.display = 'none';

if (probabilityChart) {
probabilityChart.destroy();
probabilityChart = null;
}
}

function copyResults() {
var resultText = "Genetic Calculator Results:\n\n";
var resultOutput = document.getElementById('resultOutput');
var paragraphs = resultOutput.getElementsByTagName('p');
var resultItems = resultOutput.querySelectorAll('.result-item');

if (resultItems.length > 0) {
resultText += "Genotypic Probabilities:\n";
resultItems.forEach(function(item) {
resultText += "- " + item.querySelector('.result-label').textContent + ": " + item.querySelector('.result-value').textContent + "\n";
});
} else {
resultText += resultOutput.textContent.trim() + "\n";
}

var phenotypeHeader = resultOutput.querySelector('h4');
if (phenotypeHeader) {
resultText += "\n" + phenotypeHeader.textContent + ":\n";
var phenotypeItems = resultOutput.querySelectorAll('.result-item'); // Re-selecting might grab genos too if structure is flat
// A better approach would be to have distinct classes or structure
var allResults = resultOutput.querySelectorAll('.result-item');
var phenotypeSectionStarted = false;
allResults.forEach(function(item) {
if (item.querySelector('.result-label').textContent.startsWith('Phenotype:')) {
phenotypeSectionStarted = true;
}
if (phenotypeSectionStarted) {
resultText += "- " + item.querySelector('.result-label').textContent + ": " + item.querySelector('.result-value').textContent + "\n";
}
});
}

resultText += "\nAssumptions:\n";
resultText += "- Calculations based on Punnett Square method.\n";
resultText += "- Trait type selected: " + document.getElementById('traitType').value + ".\n";
resultText += "- Assumes simple Mendelian inheritance patterns unless otherwise specified.\n";

// Clean up potential double newlines
resultText = resultText.replace(/\n\s*\n/g, '\n\n');

try {
navigator.clipboard.writeText(resultText).then(function() {
alert('Results copied to clipboard!');
}).catch(function(err) {
console.error('Failed to copy results: ', err);
prompt('Copy the text below manually:', resultText);
});
} catch (e) {
console.error('Clipboard API not available or failed: ', e);
prompt('Copy the text below manually:', resultText);
}
}

// Initial setup for potential Chart.js dependency
document.addEventListener('DOMContentLoaded', function() {
if (typeof Chart === 'undefined') {
console.warn("Chart.js library is missing. Charts will not render.");
}
});