Human Growth and Development

Here's a closer look at some common types: Autosomal chromosomal abnormalities occur in one of the first 22 pairs of chromosomes.

Autosomal Chromosome Errors

Autosomal Chromosome Mutations

Down Syndrome (Trisomy 21) is caused by an extra chromosome 21. It leads to distinct facial features, developmental delays, and an increased risk of certain health issues. With support, many individuals with Down syndrome can lead fulfilling lives into adulthood.

Phenylketonuria (PKU) is a metabolic disorder where the body can't process the amino acid phenylalanine. Early diagnosis and a special diet can manage symptoms and prevent intellectual disability. Huntington's Disease is a neurodegenerative disorder with symptoms typically appearing in mid-adulthood. There is currently no cure, but treatments can help manage symptoms. Tay-Sachs Disease is a recessive autosomal chromosome mutation that causes the death of nerve cells in the brain and spinal column. Fragile X Syndrome is caused by a mutation on the X chromosome, leading to intellectual disability, behavioral issues, and physical features like a large head and prominent ears.

Sex-linked abnormality occurs on the 23rd pair.

Sex Chromosome Abnormalities

Klinefelter Syndrome (XXY) occurs in males who have an extra X chromosome. This can lead to infertility and some developmental delays. Diagnosis can be challenging, and support is crucial. Turner Syndrome (X) occurs in females who are missing one X chromosome. This can cause learning disabilities, short stature, and infertility. Early diagnosis and intervention are essential. Genetic Testing Prenatal genetic testing helps detect genetic conditions in a developing fetus. Tests like amniocentesis, chorionic villus sampling (CVS), and non-invasive prenatal testing (NIPT) can identify chromosomal abnormalities such as Down syndrome, as well as inherited disorders like cystic fibrosis or sickle cell anemia. These tests provide valuable information for parents and doctors, but they can also raise ethical concerns and cause anxiety. Advances in non-invasive testing have made early detection safer and more accessible. Genetic testing can also reveal predispositions to certain behaviors, identifying genes linked to aggression, impulsivity, or risk-taking. However, behavior is influenced by both genetics and environment, so these tests should be interpreted with caution. Understanding genetic risk factors can help guide early interventions, but environmental factors remain crucial in shaping behavior.

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