Chromosome 4 Ring is a rare chromosomal disorder that the affected infant has a breakage of chromosome 4 at both ends, and the ends of the chromosome join together to form a ring. The amount of genetic material lost at the two ends of the chromosome may vary. Infants with very little genetic material have fewer characteristics than infants with greater amount of chromosomal ends missing. The most common features is slowed growth and development, microcephaly (small head), small jaw bones, beaked nose, cleft palate.