Miodus-Santini an 11-year-old sixth-grader from Princeton, who was classified
as autistic at only 13 months old, was never a big talker. As an infant he
didn't babble or coo. When he was a toddler beginning to speak, he would learn
one word but forget another.
brother, Christian, a 15-year-old high school sophomore, shared some similar
characteristics – difficulty with reading, processing words and speaking
clearly. Doctors said he had language impairments but was not autistic.
research published online today in the American Journal of Psychiatry, by
scientists at Rutgers University and The Research Institute at Nationwide
Children's Hospital in Ohio, reveals that there is a genetic link connecting
family members with autism like Lorenzo Miodus-Santini to those like his
brother, Christian, who have specific language impairment characterized by
speech and language difficulties that can't be explained by cognitive or
research project leader Linda Brzustowicz, Rutgers professor and chair of the
Department of Genetics, in the School of Arts and Sciences, says that genes in
a narrow region of two chromosomes (15q23-26 and 16p12) responsible for oral
and written language impairments can result in similar behavioural
characteristics with one family member developing autism and the other having
only language difficulties.
Specific language impairment
language impairment is one of the most common learning disabilities, affecting
an estimated 7% of children. It is not considered to be an autism spectrum
disorder. Autism effects one in 88 children nationally – with nearly five times
as many boys than girls diagnosed – about half of whom have some degree of
this group of families we are trying to find genetic factors that might connect
them," says Brzustowicz, who collaborated on the study with Christopher W
Bartell, principal investigator in the Battelle Centre for Mathematical
Medicine at Nationwide Children's Hospital. "This research is important
because it is hard to understand autism until we find the genes that might be
scientists don't believe that there is one single gene that causes autism but
rather a number of genes that increase the risk, Brzustowicz and her team of
researchers are working to identify genetic patterns in these families in order
to help gain a better understanding of the mechanisms that lead to autism, a
developmental brain disorder that appears in the first three years of life.
Battery of tests
Rutgers autism study, 79 families – mostly from New Jersey and Pennsylvania –
with one child with autism and at least one with specific language impairment
underwent extensive in-home testing. Besides taking blood samples for genetic
testing, family members including parents, children, and grandparents and in
some cases even uncles, aunts and cousins underwent a battery of tests to
assess grammar, vocabulary and language processing.
results indicate that there are shared patterns of DNA and visible behavioural
characteristics across our group of study families," says Judy Flax, an
associate research professor working on the study with Brzustowicz.
to the language findings, researchers also found strong evidence of a genetic
link in the areas of obsessive-compulsive, repetitive behaviours and social
interaction skills, other symptoms associated with autism.
Evidence of genetic similarities
says the next step will be to sequence the whole genome of those who
participated in the study in order to compare the families to see if scientists
can pinpoint any specific genes or mutations that are common to all.
It is part
of a long-term collaboration between scientists from Rutgers and Nationwide Children's
Hospital, as well as scientists, data experts and physicians from Rutgers,
Saint Peter's University Hospital in New Brunswick and the Rutgers University
Cell and DNA Repository (RUCDR).
and her team have been studying the genetic influences of autism on families
for the past decade – recently receiving a $2.2 million five-year grant from
the state last year. They are opening the study to new families with autism as
they continue the study over the next four years.
is just the beginning," says Brzustowicz. "We are finding evidence of
genetic similarities with the hopes of being able to identify targets that
might respond to pharmacological treatments."