ANGELMAN SYNDROME

1.) It affects chromosome 15, usually in the maternally derived chromosome. In most cases, the q12 row in chromsome 15 is deleted, resulting in the syndrome.

Normal chromosome #15 from father and mother

Deletion in maternal chromosome: occurs in 68% of individuals

2.) Angelman sydrome affects both physical and mental attributes of the individual. In 100% of the cases reported, symptoms include:

• ATAXIA OF GAIT: Loss of movement: walking
• include clumsiness or jerky motions
• HAPPY DEMEANOR
• overly laughing and smiling tendencies
• hand-flapping: hypermotoric behavior
• SPEECH IMPAIRMENT
• minimal use of words

         In 80% of cases:

• DISPROPORTIONATE HEAD GROWTH: circumference wise
• results in microcephaly: small head
• SEIZURES
• severity decreases with age

          In 20-80% of cases:

• WIDE MOUTH
• WIDE-SPACED TEETH
• DROOLING
• STRABISMUS: lazy eye
• FASCINATION WITH:
• water
• crinkly paper
• ALBINISM 

3.) This abnormality occurs most likely in the S stage of interphase before meiosis because it has to do with allele representation. This gene is only active in the maternal chromosome, so its deletion gets rid of the only copy of that gene.

WORKS CITED:
www.angelman.org
http://en.wikipedia.org/wiki/Genomic_imprinting